Improvements in Chucks for Lathes and other Machine Tools.
Year: 1898

page_text: PROVISIONAL SPECIFICATION.
Improvements in Chucks for Lathes and other Machine Tools.
I, EDWARD JONES, of the Firm of Kynoch Limited, of Lion Works, Witton,
in the County of Warwick, Engineer, do hereby declare the nature of this inven-
tion to be as follows:
This invention consists of improvements in chucks for lathes and other machine
tools, my object being to construct a convenient and easily manipulated chuck
that shall very effectually and securely grip the articles to be machined.
In constructing a chuck in accordance with my invention, I screw or otherwise
secure within the mouth of the chuck body, a steel plug which has a conical
central aperture, formed through it. The conical central aperture is made of such
a cross section as to provide rectangular recesses preferably four in number, for
the reception of a number of anti-friction rollers which are retained in position
by means of gun-metal or other cages or frames, which are arranged to contain
springs to return them to their original position each time the grip on the work
held in the chuck is released. The said cages or frames with the anti-friction
rollers arranged therein, are interposed between the interior surface of the inter-
nally tapered hollow plug hereinbefore described, and the correspondingly exter-
nally tapered surface of the four part or split central portion of the chuck form-
ing the jaws for gripping the work to be held in them.
The larger end of the conical aperture in the plug as also the larger end of the
jaws is arranged within the chuck, the smaller end of each part being at the outer
extremity.
When
The split central portion or the gripping jaws are caused to slide longitudinally
within the chuck by the action of the cam or by other suitable means.
drawn to their innermost position the rod or other article can be readily inserted
between the jaws, and the anti-friction rollers then slide freely in the annular
space between the exterior of the jaws and the plug. But when the jaws are
moved in an outward direction by the action of the cam or other operating
mechanism, the large end of the conical external surface of the jaws approaches
the small end of the plug aperture and an intense but uniform radial pressure
is thereby imposed upon the jaws causing them to grip tightly upon the bar or
other article between them and thus to effectually hold the same during the pro-
cess of machining.
1000

page_text: I, EDWARD JONES, of the Firm of Kynoch Limited, of Lion Works, Witton,
in the County of Warwick, Engineer, do hereby declare the nature of this inven-
tion and in what manner the same is to be performed, to be particularly described
and ascertained in and by the following statement:-
-
This invention consists of improvement in chucks for lathes and other machine
tools, my object being to construct a convenient and easily manipulated chuck
that shall very effectually and securely grip the articles to be machined.
In the three accompanying sheets of explanatory drawings to be hereinafter
referred to.-
Figure 1 on Sheet 1 is an elevation with part in section, representing the
running head-stock of a lathe or other machine fitted with my improved chuck.
Figure 2 is an elevation and Figure 3 an end view showing the split central
portion or the jaws of the chuck.
On Sheet 2 Figure 4 is an end view and Figure 5 a sectional side elevation
showing, to a larger scale, the arrangement of the roller frames or cages.
On Sheet 3 Figure 6 is an end view and Figure 7 a plan of one of the roller
frames or cages.
The same reference letters in the different views indicate the same parts.
In constructing a chuck in accordance with my invention I screw or otherwise
secure within the mouth of the chuck body A, a steel plug B which has a conical
central aperture formed through it. The conical central aperture, is made of
such a cross section as to provide rectangular recesses, preferably four in number,
for the reception of a number of anti-friction rollers C which are retained in
position by means of gun-metal or other cages or frames as D, such cages being
arranged to contain springs as E in the pockets D¹ to return them to their original
position each time the grip on the work held in the chuck is released; the front
ends of the springs as E abut against the plate F detachably connected to the
outer face of the plug B.
The said cages or frames D with the anti-friction rollers C arranged therein,
are interposed between the interior surface of the internally tapered hollow.
plug B hereinbefore described, and the correspondingly externally tapered surface
of the four part or split central portion G of the chuck forming the jaws for
gripping the work to be operated upon.
The larger end of the conical aperture in the plug B and also the larger end of
the jaws are arranged within the chuck, the smaller end of each part being at
the outer extremity.
The split central portion or the gripping jaws G can be caused to slide longi-
tudinally through a short distance within the chuck, and when drawn or pressed
back to their innermost position the rod or other article can be readily inserted
between the jaws. The anti-friction rollers C are then quite free in the annular
space between the exterior of the jaws G and the interior surface of the plug B.
But when the jaws are forced in an outward direction, or the direction shown by
the arrow at Figure 1, by the action of the wedge H on the central distance
piece J (such wedge being controlled by the operating sleeve K) or by the action
of other suitable mechanism, the large end of the conical external surface of
the jaws G approaches the small end of the aperture in the plug B. and an intense
but uniform radial pressure is thereby imposed upon the jaws G causing them
to grip tightly upon the bar or other article between them and thus to effectually
hold the same during the process of machining.

page_text: Having now particularly described and ascertained the nature of my said
vention and in what manner the same is to be performed, I declare that what I
claim is:.
A chuck for a lathe or other machine tool having anti-friction rollers arranged
in combination with the gripping jaws, substantially as described and as
illustrated.
1000
MARKS & CLERK,
18, Southampton Buildings, London, W.C., and
13, Temple Street, Birmingham, Agents for the Applicant.