Improvements in Rotary Chucks to be used in Lathes.
Year: 1891

page_text: Date of Application, 25th Nov., 1891
Complete Specification Left, 26th July, 1892-Accepted, 27th Aug., 1802
PROVISIONAL SPECIFICATION.
Improvements in Rotary Chucks to be used in Lathes.
I, WILLIAM FORD SMITH, Director of the firm Smith and Coventry Limited,
of Gresley Iron Works, Salford, in the County of Lancaster Engineers and Tool
Makers, do hereby declare the nature of the said invention, to be as follows :-
My invention relates to chucks arranged so that the article to be turned,
internally or externally, bored, chased or otherwise cut, may be fixed and held
securely therein and then operated upon on two, three or four sides, without being
released from the first position in which it is gripped by the chuck.
It is used for articles similar to cocks and valves, which in some cases have
junctions or other parts to be cut on two, three or four sides in the same plane. By
such chucks, cocks and similar articles can be operated upon on four sides so as to
be finished exactly true and in the same plane at one fixing.
My invention relates to an improved combination and arrangement of chuck for
the above named purpose.
It is formed by a face plate made to screw or fixed upon the end of the lathe
spindle by which it is to be rotated in the ordinary manner.
Diametrically across the face plate there is a groove and on opposite sides of the
axis a bracket is secured to the face plate by a screw or bolt.
Each bracket is bored out in a radial line at a right angle to the axis of the
lathe spindle, for the bearings of two hollow shafts or axes which form the
trunnions of a rectangular loop.
This rectangular loop and its hollow trunnions can thus be rotated.
End play is prevented by a disc on one trunnion on one side of one bearing and
screw lock nuts on the other side of the same bearing screwing on to the end of
the trunnion.
The disc secured on the inside of the bearing has notches in its edge for the
end of a catch, jointed to the bracket, to enter, which catch is held in the notch
by a spring.
These notches in the disc are at any required distance apart but are generally
90 degrees apart, and when the catch is in one notch the plane of the rectangular
loop stands at an angle of 45 degrees to the axis of the lathe spindle in which
position the sides of the rectangular loop are clear of any tools which are to
operate upon the article held within the chuck.
In the bore of each trunnion a tube fits which on its exterior has a groove in
it to fit a key secured in the trunnion.
This key allows the tube to move endways but prevents it from rotating except
with the rectangular loop.
The tube is screw threaded internally to fit a screw having a collar upon it
that enters the bore in the trunnion of the rectangular loop, which is screw
threaded at its outer end internally to receive a bush screwed therein.
Upon the screw outside the bush there is a collar secured to the screw by a pin,
and the screw is thus prevented from moving endways.
The outer end of the screw has squares formed upon it for a key, the rotation
of the screw moves the tube in or out as required.
The inner end of each tube carries a part shaped to suit the article to be gripped,
such parts having a pin or axis that enters into the end of the tube being
prevented from revolving therein by a key and key groove. These gripping parts
are intended to be changed to suit the article to be gripped, which is placed
between the parts, one in each tube in each hollow trunnion.

page_text: By this means, while the article is firmly gripped and held, the rectangular
loop can be readily turned and placed and held in any required position on its
trunnion axes, while being turned internally or externally bored, or chased.
Dated this Twenty-fourth day of November 1891.
PETER J. LIVSEY,
Agent..
COMPLETE SPECIFICATION.
Improvements in Rotary Chucks to be used in Lathes.
I, WILLIAM FORD SMITH, Director of the firm Smith and Coventry Limited,
of Gresley Iron Works, Salford in the County of Lancaster, Engineers and Tool
Makers, 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 :-
My invention relates to chucks arranged so that the article to be turned,
internally or externally, bored, chased or otherwise cut may be fixed and held
securely therein and then operated upon on two, three or four sides, without being
released from the first position in which it is gripped by the chuck.
It is used for articles similar to cocks and valves, which in some cases have
junctions or other parts to be cut, on two, three or four sides in the same plane.
By such chucks, cocks and similar articles can be operated upon on four sides so as
to be finished exactly true, and in the same plane at one fixing.
My invention relates to an improved combination and arrangement of chuck for
the above named purpose.
Fig. 1 is a front elevation, Fig. 2 is an edge or plan view and Fig. 3 is a
sectional elevation, the section being through the line A-A Fig. 1, in a plane
passing through the axis of the lathe spindle.
The chuck is formed by a face plate a, which may be prepared to screw upon the
end of the lathe spindle in the ordinary manner, or prepared to be secured to a
dise having a boss screw threaded to screw upon the end of the lathe spindle in the
ordinary manner, the disc part (not shown) being made. to fit a recess in the face
plate to which disc the latter is secured by screws or bolts, passing through
holes a', Fig. 3, as shown in dotted line in Fig. 1.
Diametrically across the face plate a, there is a groove a³, (see Figs. 2 and 3)
and on opposite sides of the axis of the face plate a bracket b, and ', is secured to
the face plate by a screw or bolt b².
Each bracket 6, and b', is bored out in a radial line at a right angle to the axis
of the lathe spindle, for the bearings of two hollow shafts or axes c', which form
the trunnions of a rectangular loop c.
This rectangular loop c, and its hollow trunnions c¹, can thus be rotated.
End play is prevented by a disc or washer c², on one side (which is secured
upon the trunnion so that it cannot revolve thereon) of one bearing and screw
nuts 3, on the other side of the same bearing (61) screwing on the end of the
trunnion.
The disc or washer c², secured on the inside of the bearing has notches c, in its
edge for the end of a catch d, jointed on a pin d', to the bracket b', to enter, which
catch d, is held in the notch by a helical spring d², placed in a hole in the bracket b¹,
(see Fig. 1) which spring d2, is arranged to push one end of the catch lever d,
outwards; d³, is the handle of the catch lever d, for releasing it from the notch in
the disc c².
These notches e, in the disc c², are at any required distance apart, but generally
90 degrees apart, and when the catch d, is in one notch, the plane of the rectangular
loop c, stands at an angle of 45 degrees to the axis of the lathe spindle (as shown
in Fig. 2) in which position the sides of the rectangular loop are clear of any tools
which are to operate upon the article held within the chuck.

page_text: In the bore of each trunnion c¹, a tube e, fits, which on its exterior has a groove
in it to fit a key e³, secured in the trunnion.
This key e², allows the tube e, to move end ways but prevents it from rotating
except with the rectangular loop c.
"
Each tube e, is screw threaded internally to fit a screw f, having a collar f¹, upon
it that enters the bore in the hollow trunnion of the rectangular loop each of
which is screw threaded at its outer end internally to receive a bush f, screwed
therein.
Upon the screw f, outside the bush, there is a collar f³, secured to the screw by
a pin, and the screw, is thus prevented from moving end ways.
The outer end of each screw f, has squares formed upon it for a key, the
rotation of the screw f, moves the tube e, in or out as required.
The inner end of each tube e, carries a part g, shaped to suit the article to be
gripped, such part having a pin or axis g, that enters into the end of the tube e,
being prevented from revolving therein by a key ², and key groove.
These gripping parts g, are intended to be changed to suit the article to be
gripped which is placed between the parts g, one in cach tube e, in each hollow
trunnion.
By this means, while the article is firmly gripped and held, the rectangular
loop c, can be readily turned and placed and held in any required position on its
trunnion axes c', while being turned internally or externally bored or chased.
The strain of gripping the article is taken by my improved arrangement entirely
upon the rectangular loop e, which can thus be freely rotated when required.
Having now particularly described and ascertained the nature of my said inven-
tion, and in what manner the same is to be performed, I declare that what I
claim is.
1. In chucks for lathes the system or mode of holding the part to be gripped
within a looped part having trunnion axes carried in bearings on a face plate,
substantially as hereinbefore described.
2. The combination and arrangement of parts forming a lathe chuck substantially
in the manner and for the purpose hereinbefore described and illustrated by the
drawings.
Dated thin Thant.. thi] C T..1 1000
PETER J. LIVSEY,
Agent.