Improvements in and relating to Certain Tools or Appliances used in Turning or Finishing Cast Metal Hollow-ware.
Year: 1895

page_text: Date of Application, 6th Apr., 1895
Complete Specification Left, 4th Jan., 1896-Accepted, 8th Feb., 1896
PROVISIONAL SPECIFICATION.
Improvements in and relating to Certain Tools or Appliances used
in Turning or Finishing Cast Metal Hollow-ware.
We, THOMAS HOLCROFT AND SONS, LIMITED, of Ettingshall Foundry, near
Wolverhampton in the County of Stafford, Cast Iron Hollowware Manufacturers
and General Ironfounders, and STEPHEN WILLIAM CHALLEN, of Derwent
Foundry, Constitution Hill, in the City of Birmingham, Engineer, do hereby
declare the nature of this invention to be as follows:-
This invention relates to milling cutters and chuck, used with other mechanism,
for the purpose of milling or finishing cast metal hollowware in the manner
substantially as described in Patent Specification Number 1619 of 1893, that is to
say, by turning out the interior surface of each hollowware article by means of a
milling cutter adapted for such purpose as described in such Specification.
In using a milling cutter of the character and in the manner described in such
Specification, the speed at which the work can be profitably accomplished, having
regard to the wear of the cutter, is limited by the heat which is engendered; and
the object of this invention is the employment of means for use in keeping the
cutter cool and thus enabling a greater amount of work to be performed in a
given time.
The above object is effected, according to this invention, by forming the milling
cutter hollow and the chuck with a hollow jacket or space between its interior and
exterior surfaces, and circulating through each of them a stream of fluid,
conveniently water, which is of course preferably cold or cool.
The method of carrying out the invention in practice is obviously capable of
variation; but the water or other fluid may be brought into the cutter or chuck by
means of a pipe which passes through the thrust-piece at the outer end of the
spindle which carries the cutter or chuck, as the case may be, and through the
whole length of the spindle, which for the purpose of this invention is formed
hollow; and the fluid may flow back along the spindle into a pipe which passes away
from the thrust-piece. A suitable fluid-tight joint or thrust bearing is, of course,
formed between the end of the spindle and the thrust-piece, such as by interposing
a leather washer between opposite surfaces of the spindle and thrust-piece,
respectively.
The construction of the chuck, also, is capable of variation. A form of
construction which answers the purpose, consists in making the chuck in two main
parts of which one part is formed with or permanently fixed to the spindle, and the
other part is formed as a collet which may be readily fixed to and removed from.
the permanently fixed part. The permanently fixed part, when the chuck is to be
used for saucepans or other articles of a barrel or bellied shape, is formed with a
sinking of which the innermost portion is shaped to receive the portion of the
article which extends from the bottom thereof to the part of largest diameter, and
of which a portion is of enlarged diameter to receive the inner portion of the
collet, and of which a portion is of still larger diameter to receive a flange formed
around the collet. The interior surface of the collet is shaped to fit around the
exterior surface of the portion of the article which projects from the innermost
portion of the sinking aforesaid, and the exterior surface of the collet is formed
with a part to fit within the aforesaid portion of enlarged diameter of such sinking,

page_text: and with a flange which fits within the aforesaid portion of still larger diameter of
such sinking, and the collet may be formed to extend outwards somewhat beyond
the collar. The article is held within the chuck by placing it first within the
permanently fixed part thereof, and then putting the collet in place around the
article and within the permanently fixed part of the chuck, and fixing it to such
part by means of dove-tail headed or corresponding bolts which have been slid in
sideways along dovetail or corresponding grooves formed in the permanently fixed
part of the chuck, and which pass also through the flange of the collet. The
permanently fixed part of the chuck is formed with a hollow space at the back
and around it, through which the cooling medium circulates.
If the chuck is for use with an article which is not barrel or bellied shaped, its
construction will be varied accordingly; and in some cases, such as when the
article is simply tapered enlarging from the bottom upwards, a collet may be
dispensed with, the chuck being formed with a recess within which the article may
be held by the aid of pins or other simple means of fixture during the operation of
the milling cutter.
Dated this 5th day of April 1905
STEPHEN WATKINS,
Wolverhampton, Agent for the Applicants..
Improvements in and relating to Certain Tools or Appliances used
in Turning or Finishing Cast Metal Hollow-ware.
We, THOMAS HOLCROFT AND SONS, LIMITED, of Ettingshall Foundry, near
Wolverhampton in the County, of; Stafford, Cast Iron Hollowware Manufacturers
and General Ironfoundere,, and STEPHEN WILLIAM CHALLEN, of Derwent
Foundry, Constitution, Hill in City of Birmingham, 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 relates to milling, cutters and chucks, used with other mechanism
or appliances, for the purpose of milling or finishing cast metal hollowware in the
manner substantially as described in Patent Specification. No. 1619 of 1893, that
is to say, by turning out the interior surface of each hollowware article by means
of a milling cutter adapted for such-purpose as described in such Specification.
In using a milling cutter of the character and in the manner described in such
Specification, the speed at which the work can be profitably accomplished, having
regard to the wear of the cutter, is limited by the heat which is engendered; and
the object of this invention is the employment of means for use in keeping the
cutter cool and thus enabling a greater amount, of work to be performed in a given
time.
The above object is effected, according to this invention, by forming the milling
cutter hollow and the chuck with a hollow jacket or space between its interior and
exterior surfaces, and circulating through each of them a, stream of fluid,
conveniently water, which is of course: preferably cold or cool. It will usually
be found sufficient to apply the invention in the case of the cutter only, but its
application in the case of the chuck, by keeping down, the. temperature. of, the
chuck and article which it carries, tends of course also, to keep down the
temperature of the cutter. Some benefit; may, consequently, be obtained even
by applying the invention in the case of the chuck only, though it is much
preferred to apply the invention in the case of the cutter whether it is applied in
the case of the chuck or not.
The method of carrying out the invention in practice is, obviously capable of
variation; but the water or other fluid may be brought into the cutter and chuck,

page_text: respectively, by means of a pipe which passes through the thrust-piece at the outer
end of the spindle which carries the cutter or chuck, as the case may be, and through
the whole length of the spindle, which for the purpose of this invention is formed
hollow; and the fluid may flow back along the spindle into a pipe which passes
away from the thrust-piece. A suitable fluid-tight joint or thrust bearing is, of
course, formed between the end of the spindle and the thrust-piece, such as by
interposing a leather washer between opposite surfaces of the spindle and thrust-
piece, respectively.
A convenient method of carrying out this invention in practice is illustrated by
the drawings herewith, of which Figure 1 is a longitudinal vertical section, taken
along the centre line of the chuck and cutter spindles, shewing such spindles
mounted in their respective head-stocks and carrying the chuck and cutter
respectively, and shewing also the thrust-pieces in transverse section taken on the
line of the common axis of the spindles.
The milled cutter C has a hollow c formed up its axis, and the cutter spindle D
is formed with a hollow or chamber d therealong. A pipe b, which is connected
in a fluid-tight manner with the thrust-piece M and is connected also with a supply
pipe e, passes through the thrust-piece M and along the axis of the spindle D and
along the hollow c of the cutter, and terminates in an open end near to the forward
end of the cutter. A square or correspondingly-shaped hole f is formed in the
outer face of the cutter C to facilitate the unscrewing of the cutter from the
spindle, and as this opening is formed through to the hollow c for convenience in
manufacture it is filled in with a plug of wood, as shewn, to close it when the cutter
is in use.
This plug is cut out when it is desired to remove the cutter from the
spindle. The open end of the pipe b is back somewhat from the inner face of the
wood plug so as to allow water to flow out freely from such end into the hollow c
of the cutter. The cutter is kept cool by a stream, preferably of water, (or it
may be other fluid, such for instance as 23 blast of cold air) which flows
through the pipe 6 into the hollow c of the cutter, and flows out again through
the hollow and the hollow d of the spindle into a hollow g formed along the
transverse axis of the thrust-piece M through which the pipe & passes, and thence
away through a hole h and pipe i. It is preferred to form the hollow c of the
cutter C of a larger diameter for the length thereof which is within the operative
portion of the cutter than the diameter of the portion which is within the spindle,
partly for convenience of manufacture and partly to ensure a larger volume of
water than would otherwise be the case to be constantly within the operative or
projecting portion of the cutter. It is preferred also to make the hollow d of the
spindle D of a larger diameter for its main length than the diameter of the portion
through the hinder end of the spindle, for convenience in manufacture. Figure 2
shews, to an enlarged scale, a detached view in section of the hinder end of the
spindle D and of the thrust-piece M, for the purpose of illustrating more clearly
than is shewn by Figure 1 the method of making a fluid-tight joint or bearing
between the spindle and thrust-piece. This is accomplished, according to the
method illustrated, by forming a recess in the inner face of the thrust-piece M
within which a leather washer j is placed. This washer is of such thickness before
it is placed in position that when the metallic bearing surfaces of the spindle and
thrust-piece, respectively, are in contact, that is to say, when the thrust-piece has
been properly tightened up against the hinder end of the spindle, the washer is
wholly compressed into the recess. The washer may be let into a recess formed in
the hinder face of the spindle D, instead of into a recess in the face of the thrust-
piece M, or the recess for receiving the washer may be formed partly in the
hinder end of the spindle and partly in the inner face of the thrust-piece. The
annular channel k, formed partly in the face of the hinder end of the spindle D
and partly in the inner face of the thrust-piece M, is merely for the reception of
oil, which is supplied thereto through a duct l.
Figure 3 is a side elevation of the chuck and of a short length of the spindle
which carries it.

page_text: Figure 4 is a front elevation of the chuck, with the removable portion or collet
hereinafter described omitted.
Figure 5 is a front view of the complete chuck with a saucepan body secured
therein.
Figure 6 is an enlarged detail section shewing a provision for enabling the collet
to be readily loosened from the other portion of the chuck.
In Figure 1 a sectional view of a saucepan body R, held in position within the
chuck, is indicated by broken lines.
The construction of the chuck is capable of variation, but that illustrated will
be found convenient. According to this construction, the chuck is formed in two
main parts, of which the part N is conveniently formed, as shewn, with the
spindle O, and the other part P is formed as a collet which may be readily fixed
to and removed from the permanently fixed part or body N. The part N, when
the chuck is to be used for saucepans or other articles of a barrel or bellied shape,
is formed with a sinking m, of which the innermost portion n is shaped to receive
the portion of the article which extends from the bottom thereof to the part of
largest diameter, of which a portion o is of enlarged diameter to receive the inner
portion of the collet P, and of which a portion p is of still larger diameter to
receive a flange formed around the collet. The interior surface of the collet P is
shaped to fit around the exterior surface of the portion of the article which
projects from the innermost portion n of the sinking m, and the exterior surface
of the collet is formed with a part q to fit within the portion o of the sinking m,
and with a flange which fits within the portion p of the sinking m; and the collect
may be formed with a portion & which extends outwards somewhat beyond the
collar r.
Radial, dovetail or corresponding grooves t, are formed in the outer face
of the portion N and in the face or shoulder formed between the interior
surfaces and o thereof, and extend from the outer edge of the chuck to the
interior surface of the part o; and slots t¹ are formed in from the outer edge of the
flange of the collet. An opening a¹ is formed through one side of the collet to
clear the handle socket or snug b' of the saucepan body.
The saucepan body R is held within the chuck by placing it first within the
permanently fixed part N thereof, and then putting the collet in place around the
saucepan body R and within the part N of the chuck, and fixing it to such part by
means of dovetail-headed or corresponding bolts c¹ which have been slid in
sideways along the groovest and slots t¹. In Figure 5, 'the nuts on the outer ends
of two of these bolts are omitted for the sake of clearly shewing the corresponding
slots. To facilitate loosening the collet from the other portion of the chuck, inclined
surfaces d' (Figures 5 and 6) are formed at opposite points of the circumference
of the flanger of the collet, and corresponding portions e of the inner edge of
the outer face of the portion N of the chuck are inclined as shewn by Figure 6,
and thus a wedge-shaped instrument can be driven in between the inclined
surfaces de to force out the collet.
The spindle O is formed hollow, as shewn, and the portion N of the chuck is
formed with a hollow space f¹ between its hinder face and the inner face of the
recess m, and also with an annular hollow space f which extends forwards from the
hollow space f¹ and surrounds a considerable portion of the recess m.
The hollow
of the spindle O is carried into the hollow space f¹ of the chuck, as shewn, and
water (or other fluid) is brought through a pipe g' into the hollow space of the
chuck, and the chuck is consequently kept cool by a stream of water which flows in
by such pipe and out again through the hollow of the spindle O, and thence away.
The means of bringing the water into the chuck and conveying it therefrom, and
of making a fluid-tight thrust bearing between the hinder end of the spindle O and
the thrust-piece M', correspond with those above described in connection with the
cutter C and spindle D.
To ensure that the bolts c' will remain within the outer portions of the grooves t
of the portion N of the chuck, after the bolts have been moved outwards to clear
the slots of the collet, each bult may be provided with a spiral spring h¹ (see

page_text: enlarged sectional view Figure 7 of one of the bolts and grooves) let into a recess¹
in the inner end of the bolt. The pressure of the spring puts sufficient friction
upon the portion of the bolt within the dovetail, or corresponding portion of the
groove, to cause it to be held in position within the groove into whatever position.
the groove itself may have been turned. It is thus not necessary to remove the
bolts from the grooves when the collet is to be removed and to replace them when
the collet is to be refixed.
If the chambered or jacketed chuck is for use with au article which is not barrel
or bellied shaped, its construction will of course be varied accordingly. A modified
form of chuck for use with a tapered-sided (or it may be a straight-sided) article
is shewn in section by Figure 8, which is a corresponding section of the chuck to
that shewn by Figure 1 of the chuck for use with a bellied-shaped article. In this
case, the collet P is let into a plain recess formed in the face of the portion N' of
the chuck, and is held therein by bolts as in the case of the collet P. The collet P¹
is formed with a rim k¹ which projects partly across the outer edge of the article R¹
and thus securely holds the article back within a recess formed to receive it in the
portion N' of the chuck.
Having now particularly described and ascertained the nature of our said inven-
tion, and in what manner the same is to be performed, we declare that what we
claim is :-
:-
1. A milling cutter, for milling or finishing cast metal hollowware in the manner
substantially as described in Patent Specification No. 1619 of 1893, formed hollow
and used in combination with other appliances whereby a stream of fluid may be
allowed to flow into and from such cutter for the purpose of keeping down the
temperature thereof in working, substantially as described.
2. A chuck, for use in milling or finishing cast metal hollowware iu the manner
substantially as described in Patent Specification No. 1619 of 1893, formed with a
fluid chamber or jacket and used in combination with other appliances whereby a
stream of fluid may be allowed to flow into and from such chamber or jacket for
the purpose of keeping down the temperature of the chuck in working and thus
tending to keep down also the temperature of the cutter, substantially as
described.
3. The combination of a hollow milling cutter, a hollow spindle for same, a pipe
which forms a fluid-tight connection with the thrust-piece and extends along the
axis of the spindle and terminates in position to supply a streain of fluid to the
interior of the cutter, a suitable outlet from the thrust-piece for the outflow of fluid
from the cutter, and a fluid-tight bearing between the hinder end of the spindle and
the thrust-piece, all substantially as described.
4. The combination of a chuck formed with a fluid chamber or jacket, a hollow
spindle for same, a pipe forming a fluid-tight connection with the thrust-piece and
extending along the axis of the spindle and terminating in position to supply. a
stream of water to the chamber or jacket of the chuck, a suitable outlet from the
thrust-piece for the outflow of fluid from the chuck, and a fluid-tight bearing
between the hinder end of the spindle and the thrust-piece, all substantially as
described.
Dated this 3rd day of January 1896.