Improvements in the Apparatus known as Spherical Chucks or Dome Chucks, and used in conjunction with Lathes, more particularly such Lathes as are used for. Ornamenting Wood, Ivory, Metal, and other Materials.
Year: 1890

page_text: Date of Application, 24th Dec., 1890--Accepted, 14th Feb., 1891
COMPLETE SPECIFICATION.
Improvements in the Apparatus known as Spherical Chucks or
Dome Chucks, and used in conjunction with Lathes, more
particularly such Lathes as are used for. Ornamenting Wood,
Ivory, Metal, and other Materials.
I, GEORGE BIRCH of Islington Tool Works, Islington Grove, Salford, in the
County of Lancaster, Engineer and Tool Maker, 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 the apparatus known as spherical chucks or dome chucks
and used in conjunction with lathes more particularly such lathes as are used for
ornamenting wood, ivory, metal, and other materials and my invention consists in
means enabling "work" of certain kinds to be more readily done by means of such
spherical chucks or dome chucks than heretofore and rendering such spherical
chucks or dome chucks more convenient in use than they have hitherto been.
"
In spherical chucks or dome chucks as hitherto constructed although the "work"
could be readily moved in a direction away from the axis of the mandrel or "spindle
by which it was supported and upon which it was oscillated such work could not be
brought into line with the axis of the said mandrel or spindle.
,,
In a spherical chuck or dome chuck constructed according to my invention the
"work
can not only be moved to and from the axis of the mandrel or spindle
upon which it is mounted but may be moved across and to a certain distance beyond
the axis of the mandrel or spindle upon which it is mounted thus enabling work to
be accomplished by means of the chuck which either could not be accomplished or
could only be accomplished with difficulty in spherical chucks or dome chucks as
hitherto constructed.
My invention is shown in the accompanying drawing in which Fig. 1 is a front view
Fig. 2 a side view and Fig. 3 a plan partly in section showing so much of a spherical
chuck or dome chuck as is requisite to illustrate my invention.
a is the mandrel or spindle upon which the base of the spherical chuck or dome
chuck is mounted. Upon the base bare formed slides carried by which and
capable of being slidden longitudinally therein or thereon is the slide d upon which
is mounted the part e which can be rotated around the axial line A. A. by means of
the tangent screw f and worm wheel g. The slide d is capable of being moved.
longitudinally in or upon the slides c by means of the screw which is provided
with a milled head by which it may be turned. After the slide d has been
adjusted into the desired position by the screw it may be secured in such
position by means of the screw i by which the loose strip or V piece c¹ is pressed
against the slide d. Before the slide d is moved the screw i must be "slackened."
By extending the part of the base and the part d' of the slide d beyond the
axis B B of the mandrel or spindle a I enable the "work"
upon the "chuck" to
be placed in line with or in a position beyond the axis B B of the mandrel or
spindle a.
ог
"
By extending the part of the base and part d' of the slide d"above
beyond the axis B B of the mandrel or spindle a the chuck is rendered compact in
form and is enabled to be employed either in a lathe the "height" of the "centres
of which from the lathe bed is indicated by the line CC or in a lathe the "height
of the " centres of which from the lathe bed is indicated by the line D D.
22
"
Spherical chucks or dome chucks constructed according to my invention may
thus be applied to different lathes having different heights of "centres."

page_text: 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 :-
:-
A spherical chuck or dome chuck constructed and arranged as hereinbefore
described so that the "work" may be placed in line with or beyond the axis of the
mandrel or spindle upon which such spherical chuck or dome chuck is mounted and-
so that the said spherical chuck or dome chuck is applicable to lathes having
different "heights of centres."
Dated this Twenty-third day of December 1900
W. T. CHEETHAM,
Manchester, Agent to the Applicant.