IMPROVEMENTS IN LATHES
Year: 1884

page_text: I, SAMUEL PEARCE WILDING, of the firm of Fell and Wilding, of 23 Rood Lanc,
in the City of London, Patent Agents, do hereby declare the nature of the said
Invention for "IMPROVEMENTS IN LATHES," to be as follows:-
The said Invention relates to headstocks of lathes, and is designed to prevent
any end movement in the headstock spindle, after considerable wear and tear of
the journals has taken place.
The present method of mounting headstock spindles in two bearings of a
headstock, coned in opposite directions to one another, is not efficient in preventing
the spindle from sliding forwards towards the work, and consequent looseness and
chattering in that journal nearest to the work. This effect is particularly liable to
ensue, when the weight of the object, and the pressure of the tool is considerable,
as the pressure against the inclined face of the bearing tends to wedge forward the
spindle out of the said bearing. After such a movement has taken place the
spindle will run unnecessarily heavily in its inclined back bearing which is little
engaged, and will shake or chatter in the front conical bearing which is heavily
engaged and thus affect the accuracy and quality of the work.
To remedy these disadvantages, a screw thread is cut upon a spindle of the
headstock, either between the stepped cone and cogwheel used for the back gearing,
or between the latter cogwheel and the inner face of the front headstock bearing.
Upon this thread is fitted a nut, which is provided with suitable external indents,
so that it can be rotated by a claw spanner, when required.
In that case in which the nut is situated between the stepped cone and the
cogwheel, the nut is rotated so as to press the said cogwheel upon the inner face of
the headstock front bearing. This serves to keep the coned journal of the
headstock spindle home in its front bearing and to prevent any possibility of
chattering therein. Should wear take place, the nut can be screwed up so as still
to press the coned journal home in its bearing. The nut is provided with a flange,
which embraces and locks upon a coned face of the cogwheel against which it is
screwed, and is thus prevented from slacking back by the reversal of rotation.
In the other case where the nut is applied between the cogwheel and the front
bearing of the headstock, a collar is placed between the said nut and the inside
[D-Ը 1

page_text: face of the front headstock bearing. The said collar revolves with the headstock
spindle by a slot and feather.
In the improved headstock also, the back coned bearing has a conicity in the
same direction as that of the front bearing, and the brass sleeve which is coned
inside is parallel externally, and adjusted in the back headstock by a nut on either
side of the bearing. When the headstock spindle is drawn back by the intermediate
nut to take up wear and tear in the front bearing, the back bearing can be set free
to follow the movement of the said spindle, and be afterwards locked in place.
Dated this 7th day of April A.D. 1884.

page_text: I, SAMUEL PEARCE WILDING of the firm of Fell and Wilding, of 23 Rood. Lane,
in the City of London, Patent Agents, do hereby declare the nature of the said
Invention for "IMPROVEMENTS IN LATHES," and in what manner the same is to be
performed, to be particularly described and ascertained in and by the following
statement:-
The said Invention relates to headstocks of lathes, and is designed to prevent
any end movement in the headstock spindle, after considerable wear and tear of
the journals has taken place.
The present method of mounting headstock spindles in two bearings of a
headstock, coned in opposite directions to one another, is not effecient in preventing
the spindle from sliding forwards towards the work, and consequent looseness and
chattering in that journal nearest to the work. This effect is particularly liable to
ensue, when the weight of the object, and the pressure of the tool is considerable,
as the pressure against the inclined face of the bearing tends to wedge forward the
spindle out of the said bearing. After such a movement has taken place the spindle
will run unnecessarily heavily in its inclined back bearing which is little engaged,
and will shake or chatter in the front conical bearing which is heavily engaged,
and thus affect the accuracy and quality of the work.
To remedy these disadvantages, a screw thread is cut upon a spindle of the
headstock, either between the stepped cone and cogwheel used for the back
gearing, or between the latter cogwheel and the inner face of the front headstock
bearing. Upon this thread is fitted a nut, which is provided with suitablo external
indents, so that it can be rotated by a claw spanner when required.
In that case in which the nut is situated between the stepped cone and the
cogwheel, the nut is rotated so as to press the said cogwheel upon the inner face of
the headstock front bearing. This serves to keep the coned journal of the
headstock spindle home in its front bearing and to prevent any possibility of
chattering therein. Should wear take place the nut can be screwed up so as still
to press the coned journal home in its bearing. The nut is provided with a flange,
which embraces and locks upon a coned face of the cogwheel against which it is
screwed, and is thus prevented from slacking back by the reversal of rotation.
In the other case where the nut is applied between the cogwheel and the front
bearing of the headstock, a collar is placed between the said nut and the inside face
of the front headstock bearing. The said collar revolves with the headstock
spindle by a slot and feather.
In the improved headstock also, the back coned bearing has a conicity in the
same direction as that of the front bearing, and the brass sleive which is coned
inside is parallel externally, and adjusted in the back headstock by a nut on either
side of the bearing, when the headstock spindle is drawn back by the intermediate
nut to take up wear and tear in the front bearing, the back bearing can be set free
to follow the movement of the said spindle, and be afterwards locked in place.
In order that my Invention may be the better understood, I now proceed to
describe the same in relation to the Drawings hereunto annexed, reference being
Lad to the letters and Figures marked thereon.
Like letters refer to like parts.
Between the wheel A. of the stepped pulley B. Fig. I, a flat nut m is screwed on
the spindle, which is screw threaded at this part in such a manner that the boss
surface of the wheel A. presses slightly against the back breast surface of the front
poppet head, the touching surfaces being well planed; in this way the spindle is

page_text: effectually prevented from leaving the conical front bearing, and consequently
chattering in the latter.
To obviate the loosening of the nut, while the step pulley is rapidly rotating to
the left, it is provided with a rim (shown in detail in Fig. 3) which grips the
back surface of the boss of the gearing wheel. When wear of the front bearing
has taken place, the spindle can be adjusted by the screwing up of the nut.
For this purpose the rim r is formed with recesses S for the reception of a
wrencli.
To prevent this spindle, moved towards the back poppet, from getting air in the
cone of the latter-This cone is (differently from the usual method) placed in the
same sense as the cone of the front poppet; so that, by the sliding of the spindle, a
better lock is also obtained in the bearing of the back poppet; but as this usually.
shows less wear than the front poppet, the spindle might easily be braked in the
former, to obviate which the bearing in the back poppet is adjustable by means of
nuts n of the screw threaded ends of the bearing. Fig. 2. shows a modification of
the before described construction in which, instead of employing the gearing
wheel A, a separate adjusting ring L is used which is fixed by means of a groove
and tongue, and pressed against the poppet by means of the nut m'.
Having now. particularly described and ascertained the nature of my said
Invention and in what manner the same is to be performed I declare that what
I claim is
In lathes the combination of a nut m or m³ with the gearing wheel A or the
adjusting ring L to secure and maintain the spindle in position substantially as and
Dated this 13th day of August 1884.
FELL & WILDING,
Agents for the Applicant.