are also Applicable to Vices and to Cramps.
Year: 1887

page_text: are also Applicable to Vices and to Cramps.
We CHARLES TAYLOR and GEORGE BENJAMIN TAYLOR both of Edmund Street
Birmingham in the County of Warwick Machinists do hereby declare the nature of
this Invention to be as follows:
Our invention consists principally of the improvements hereinafter described in such
chucks for lathes as are commonly called scroll-chucks and screw chucks but our
improvements are also in part applicable to the jaws of vices and to cramps as herein-
after described.
We will describe our improvements in connection with chucks for lathes.
Instead of making the face of the chuck flat as usual we give to the said face the
figure of an obtuse hollow cone and we give to the ways in the body of the chuck in
which ways the jaws work an inclination to the axis of the chuck similar to that of the
The
sides of the said cone that is the said ways are parallel to the sides of the cone.
jaws of the chuck may be of any desired shape and actuated in any of the ordinary
ways. We prefer however to actuate the jaws by means of a spiral scroll disc the
face of the said disc on which the scroll is made having a hollow conical figure similar
to the figure of the face of the chuck. The thread of the spiral scroll may be of any
angle but preferably we make the inner face of the thread parallel to the axis of the
chuck and the other face of the thread either at right angles to the former or at an
angle of forty five degrees thereto according to the purpose for which the chuck is to
be employed. When the chuck is employed for holding drills or wire or articles of
small diameter we prefer to make the sides of the thread of the spiral scroll at right
angles. When the chuck is to be used for holding articles of large diameter the outer
side of the thread of the spiral may be inclined to the inner side of the thread at an
angle of forty five degrees.
The teeth of the jaws have a figure the counterpart in cross section of the cross
section of the thread of the spiral. By the rotation of the spiral scroll disc in one or
other direction the jaws may be made to converge to or diverge from the axis of the

page_text: chuck and a tool or article thereby fixed in or liberated from the chuck. This rotation
of the said disc may be effected by a bevil pinion engaging in a bevil wheel formed
on the underside of the spiral scroll disc. Or the scroll disc may be held still and the
body of the chuck rotated upon it.
Instead of making the face of the chuck of the figure of an obtuse hollow cone it
may be made of a curved hollow or bowl shape. The ways in the body of the chuck
and the jaws are in this case made of a similar figure. By this modification the
support of the teeth is brought nearer to the resistance than when the face of the
chuck is conical.
A chuck having the ways in which the jaws work inclined as hereinbefore described
may have its jaws actuated by screws capable of an axial motion but incapable of
motion in the line of their axes. In this case we prefer to give the thread of the
screw such as a figure that in a section of the chuck taken in a plane in which its axis
is situated the section of the inner faces of the thread is parallel to the axis of the
chuck. The outer face of the thread may either be at right angles to the inner face
or make an angle of forty five degrees therewith. Instead of making the face of the
chuck of the figure of a concave or hollow cone it may have the figure of a convex
cone or conical shell. In this case the interior of the conical shell has the spiral
scroll made upon it the sides of the thread being respectively parallel to the axis and
face of the chuck. The teeth of the jaws of the chuck have a figure corresponding
to the figure of the spiral scroll.
By making the faces of the thread of the spiral scroll and the teeth of the jaws in
the ways described the said threads are not liable to be stripped under great pressure
as the face by which the pressure is borne is at right angles to the pressure and is
firmly backed up or supported.
When we actuate the spiral scroll by means of levors we prefer to employ two of
the said levers situated in holes one in the spiral scroll disc and one in the body of
the chuck the said holes being parallel with and on opposite sides of a diameter of the
scroll. The said levers consist of rods, capable of sliding in the said holes. The said
rods have a knob at each end and the holes are contracted near their outer ends so
that the rods can only be drawn out or pushed in to the required distance. The rods
are temporarily fixed in the positions to which they have been brought by light
springs.
The improvements described with respect to the relative positions of the faces of
the thread of the spiral scroll and the teeth of the jaws are applicable to the screws
and screw boxes of vices and cramps.
Dated this Eighteenth day of October 1887

page_text: are also Applicable to Vices and to Cramps.
We CHARLES TAYLOR and GEORGE BENJAMIN TAYLOR both of Edmund Street
Birmingham in the County of Warwick Machinists do hereby declare the nature of
our Invention and in what manner the same is to be performed to be particularly
described and ascertained in and by the following statement :—
Our invention consists principally of the improvements hereinafter described in
such chucks for lathes as are commonly called scroll chucks and screw chucks but our
improvements are also in part applicable to the jaws of vices and to cramps as
hereinafter described.
We will describe our improvements in connection with chucks for lathes.
Instead of making the face of the chuck flat as usual we give to the said face the
figure of an obtuse hollow cone and we give to the ways in the body of the chuck, in
which ways the jaws work, an inclination to the axis of the chuck similar to that of
the sides of the said cone, that is, the said ways are parallel to the sides of the cone.
The jaws of the chuck may be of any desired shape and actuated in any of the
ordinary ways.
We prefer however to actuate the jaws by means of a spiral scroll
disc, the face of the said disc on which the scroll is made having a hollow conical
figure similar to the figure of the face of the chuck. The thread of the spiral scroll
may be of any angle but preferably we make the inner face of the thread parallel to
the axis of the chuck and the other face of the thread either at right angles to the
foriner or at an angle of forty five degrees thereto according to the purpose for which
the chuck is to be employed. When the chuck is employed for holding drills or wire
or articles of small diameter we prefer to make the sides of the thread of the spiral
scroll at right angles. When the chuck is to be used for holding articles of large
diameter the outer side of the thread of the spiral may be inclined to the inner side
of the thread at an angle of fifty five degrees. The teeth of the jaws have a figure
the counterpart in cross section of the cross section of the thread of the spiral. By
the rotation of the spiral scroll disc in one or other direction the jaws may be made
to converge to or diverge from the axis of the chuck and a tool or article thereby
fixed in or liberated from the chuck. This rotation of the said disc may be effected
by a bevil pinion engaging in a bevil wheel formed on the underside of the spiral
scroll disc. Or the scroll disc may be held still and the body of the chuck rotated
upon it.
Instead of making the face of the chuck of the figure of an obtuse hollow cone it
may be made of a curved hollow or bowl shape. The ways in the body of the chuck
and the jaws are in this case made of a similar figure. By this modification the
support of the teeth is brought nearer to the resistance than when the face of the
chuck is conical.
A chuck having the ways in which the jaws work inclined as hereinbefore described
may have its jaws actuated by screws capable of an axial motion but incapable of
notion in the line of their axes. In this case we prefer to give the thread of the

page_text: screw the usual angle of a V thread with each other and with the axes of the screws
so that in a section of the chuck taken in a plane in which its axis is situated the
section of the inner faces of the thread is nearly parallel to the axis of the chuck.
Instead of making the face of the chuck of the figure of a concave or hollow cone
it may have the figure of a convex cone or conical shell. In this case the interior of
the conical shell has the spiral scroll made upon it, the sides of the thread being
respectively parallel to the axis and face of the chuck. The teeth of the jaws of the
chuck have a figure corresponding to the figure of the spiral scroll.
By making the faces of the thread of the spiral scroll and the teeth of the jaws in
the ways described, the said threads are not liable to be stripped under great pressure
as the face by which the pressure is borne is at right angles to the pressure and is
firmly backed up or supported.
The levers ordinarily employed may be used for actuating the spiral scroll.
The improvements described with respect to the relative positions of the faces of
the thread of the spiral scroll and the teeth of the jaws are applicable to the screws
and screw boxes of vices and cramps.
We will now proceed to describe with reference to the accompanying Drawings the
manner in which our invention is to be performed.
Figures 1, 2 and 3 illustrate a self-centring lathe chuck constructed according to
our invention having three jaws, Figure 1 representing partly in elevation and partly
in section the said chuck; Figure 2 a front elevation of the face of the said chuck,
one of the jaws being omitted for exhibiting the spiral screw within the body and
Figure 3 a section taken through the line A B Figure 1 exhibiting one of the jaws
in position.
The same letters of reference indicate the same parts, in Figures 1, 2 and 3.
A is the hollow body or case of the chuck attached to the back plate B by means of
pins as usual (not shown in the Drawing). The said body or case A has its front face
made of the figure of an obtuse hollow cone and the ways or slots C, C, C in the said
body in which ways or slots the jaws E E of the chuck work are inclined to the axis D
of the chuck at the same angle as the face of the said hollow conical body. Tho
said jaws E E are capable of free movement in the ways CC and are actuated by the
spiral screw or scroll on the concave front face of the disc F the face of which disc
makes a similar angle with the axis of the chuck as the front face of the chuck. Tho
threads of the disc F gear into corresponding threads formed upon the backs of the
jaws E E. The spiral screw disc F is actuated by one of the three pinions (two of
which G, G are shown) gearing with teeth formed upon the back of the spiral screw
disc F. When one of the pinions G, G is turned by means of a screw key or other-
wise, the jaws E, E, E are caused to converge or diverge uniformly to or from the
axis D according as the pinion is turned to the right or left hand, thus gripping or
releasing an article placed between the jaws E, E, E. Or the spiral screw F may bo
actuated by levers or by other means. The threads upon the spiral screw F may be
of any convenient shape but preferably we make them of the figure represented that
is, the inner faces parallel with the axis D of the chuck and the outer faces at an angle
of 55 degrees with the inner faces. The outer parts of the jaws are shown stepped
but they may be otherwise shaped to accommodate the article to be held by the
chuck.
Figures 4, 5 and 6 illustrate a modified form of chuck constructed according to our
invention the said chuck having four jaws and being actuated by four independent
screws. Figure 4 represents the chuck partly in elevation and partly in section,
Figure 5 a front elevation of the same, one of the jaws being omitted to exhibit the
screw beneath and Figure 6 represents a section of a portion of the same taken
through the line A2, B2 showing one of the jaws in position.
The same letters of reference indicate the same parts in Figures 4, 5 and 6.
H is the cylindrical body of the chuck having its face made of a hollow conical
form as described with respect to the chuck Figures 1, 2 and 3. The said body H has
four radial slots I, I, I, I made in it forming the ways which are cut at a similar angle
to the conical face of the chuck. Within the slots or ways I, I, I, I are fitted and

page_text: work the four jaws J, J, J three only of which are shown. The said jaws are free to
slide along the slots or ways and are actuated independently of each other by the four
screws K, K, K, K which lie in recesses cut in the body H beneath each slot. The
jaws J, J have screw threads cut upon their backs to engage with the threads upon
the screws KKKK. The threads may be of any convenient form but preferably
in this case we make their faces of the usual angle with each other and with the axes
of the screws. The outer parts of the jaws are stepped but may be shaped to
accommodate the article intended to be held by the chuck.
Figures 7, 8 and 9 illustrate a modification of a self centring chuck constructed
according to our invention, the said chuck having three jaws but its actuating screw is
formed in the interior of a hollow cone or conical shell external to and working upon
the body of the chuck: Figure 7 represents the chuck partly in elevation and partly
in section showing the jaws partly projecting; Figure 8 represents a front elevation
of the body without the cap and retaining ring the jaws being in position and Figure 9
represents a section of a portion of the same taken through the line A³, B3 Figure 7,
showing one of the jaws in position.
The same letters of reference indicate the same parts in Figures 7, 8 and 9. In this
modification the cylindrical body L of the chuck is of a truncated conical form at front
and has an axial hole of a size suitable for the largest diameter of work intended to be
held by it. The rear of the said axial hole is enlarged and is made conical as shown in
Figure 7 for attachment to the machine it is intended for. The body L has three
radial slots cut in its conical front, the bottoms of the said slots being parallel with the
conical face of the body. In the said slots or ways the jaws M, M, M work and are
actuated simultaneously by the internal spiral screw cut on the inner face of the
hollow cone or shell N, the said internal spiral screw engaging with corresponding
threads cut upon the outer edges of the jaws M, M, M. The rear of the hollow cone
or shell N is made cylindrical and fits upon the cylindrical part of the body L and is
held in position by the ring O threaded upon its rear end and abutting against a
shoulder formed upon the body L of the chuck see Figure 7. The ring O and shell N
are milled on their circumferences for convenience in turning them by the hand, or
the said ring and shell may be turned by levers or by other means.
By an examination of the several figures of the drawings it will be seen that the
transmission of pressure from the spiral screw or other screw to the screw threads or
teeth on the jaws of the chuck is effected between surfaces at right angles to the line
of pressure or parallel to the axis of the chuck as will be readily understood by
reference to the screw threads represented in section in Figures 1, 4 and 7. By
making the faces of the acting screw threads and the screw threads or teeth on the
jaws in the ways described and represented the said threads and teeth are not liable to
be stripped under great pressure as the face by which the pressure is borne is at right
angles to the direction of the pressure and is firmly backed up or supported.
The improvements described and represented with respect to the relative positions
of the faces of the screw thread or threads of the spiral screw and the teeth of the
jaws of chucks are applicable to the screws and screw boxes of vices and cramps but
we do not consider it necessary to describe and represent vices and cramps containing
the improvements in screw threads referred to as we believe that any one conversant
with the manufacture of vices and cramps will be able to apply the improvements in
screw threads to vices and cramps from the description and representation herein
given of their application to chucks.
Having now particularly described and ascertained the nature of our invention and
the manner in which the same is to be performed we declare that we claim as our
invention of "Improvements in chucks for lathes, parts of which improvements are
also applicable to vices and to cramps
رو
:-
First A chuck for lathes having two three or more jaws, the face of the said
chuck having the figure of a hollow cone, the ways in which the jaws work being
parallel to the face of the chuck substantially as herein before described and illustrated
in Figures 1, 2, 3, 4, 5 and 6 of the accompanying Drawings.

page_text: Secondly-A rotating disc for actuating the jaws of a chuck the acting face of the
said disc having the general figure of a hollow cone, one or more spiral screw threads
being cut upon
the interior of the said hollow cone for engaging with corresponding
screw threads on the backs of the jaws of the chuck the ways in the body of the chuck
making with the axis of the chuck the same angle as the face of the hollow cone makes
with the said axis substantially as herein before described and illustrated in
Figures 1, 2 and 3 of the accompanying Drawings.
Thirdly The combination in a chuck the face of which has the figure of a hollow
cone of screws for actuating the jaws of the chuck the axes of which screws make with
the axis of the chuck the same angle as the face of the chuck makes with the said axis
the said screws being capable of rotary motion but incapable of a sliding motion or
motion in the line of their axes substantially as herein before described and illustrated
in Figures 4, 5 and 6 of the accompanying Drawings.
Fourthly Actuating the jaws of the chuck by means of a spiral screw thread made
on the inner face of a hollow cone or conical shell the said spiral screw thread engaging
with teeth made on the outer faces of the said jaws substantially as herein before
described and illustrated in Figures 7, 8 and 9 of the accompanying Drawings.
Fifthly Making the screw threads on the jaws of chucks as well as the spiral or
other screw threads engaging with them and giving motion to them of the several
forms described and illustrated in the several Figures of the Drawings so that the
pressure exerted by the spiral screw or screw thread in giving motion to the jaws
shall be transmitted through surfaces at right angles to the direction of the pressure
substantially as described and illustrated.
Lastly The application to the screws and screw boxes of vices and cramps of screw
threads the acting faces of which are at right angles to the direction of the pressure as
herein before described and illustrated in the accompanying Drawings.
Data way of oury 1000.
CHARLES TAYLOR.
GEORGE BENJAMIN TAYLOR.