Improvements in Ball Grinding Machines.
Year: 1898

page_text: Date of Application, 29th Oct., 1898-Accepted, 3rd Dec., 1898
Improvements in Ball Grinding Machines.
We, PAUL ZSCHILLE and GUSTAV ADOLPH WINKLER, of Grossenhain, Saxony,
Germany, Factory Proprietors, 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 :—
This invention has for object to provide a machine which will grind balls from
the rough to a finished state and to a perfectly spherical form and to the samė
size.
In the accompanying drawing Fig. 1. is a vertical section of so much of the
machine as is necessary to explain the invention and Fig. 2 a plan view of the same
Figs. 1 and 2ª are
with some of the upper portion shewn in Fig. 1 omitted.
similar views but modified as regards the form and arrangement of the ball holding
groove. Fig. 3 is an underneath view on an enlarged scale of one of the ball
holding rings with a ball thereon and Fig. 4 is a vertical section on an enlarged
scale of the ball holding rings and of the driving ring, said Figs. 3, 4, having
reference to the modified construction. Referring to Figs. 1 and 2:-a, b, are
two stationary steel rings formed-of a number of segments the opposite edges of
which are obliquè so as to provide an open space in which the balls P to be ground
are placed, said opposite edges of the rings being a slight distance apart so that a
C is a rotary
small portion of the surface of the balls may protrude therefrom.
ball driving ring fixed on a plate projecting from a hollow shaft W which is rotated
by means of gearing or by any other suitable means and pressed upwards by a
spring (not shewn) to force the balls against the oblique surfaces of the rings a, b,
and cause said balls to protrude slightly through the cleft between the two rings.
R is a grinding ring held in a plate T fixed on a vertical shaft t arranged in a hollow
standard eccentrically to the hollow cylinders W, W₁ the latter of which carries the
ring b. In this way the whole of the grinding surface of the wheel R is brought
into action and is thereby caused to wear away equably. Said grinding ring may
be pressed down by spring pressure or adjusted by any suitable means but the
pressure of the driving ring C must be sufficient to drive the balls without being
stopped in their rotary or turning movements or clogged by said grinding ring R
which rotates in a direction opposite to that of the driving ring C., The form of
the ball holding grooves is polygonal in plan view, such form causing the balls so
to roll round in all directions with their vertical and horizontal axes continually
altering their position that their whole surface is subjected to the grinding action
of the ring R and are all ground to the same size and perfectly spherical.
In the modification shewn in Figs. 1ª, 2ª, 3, 4, where the same reference letters
as in Figs. 1, 2, are employed to indicate like or equivalent parts, the steel ball
holding rings a, b, have formed between them a circular groove but only the inner
ring a is stationary. The ring b is rotated by any suitable means through the
cylinder W¹ and in a direction contrary to that of the grinding ring C. Said
ring b is provided on its oblique ball holding surface with a projecting part u by
which, in the rotation of the ring, the balls are turned round on their vertical axes
and also so that their horizontal axes continually change their position.

page_text: When the balls in process of being ground vary somewhat in size, the smaller
ones will roll along unacted upon until the larger ones are ground down to the
smaller size whereupon the smaller balls are also pressed to project from the ball
holding groove and be ground by the ring R.
Having now particularly described and ascertained the nature of our said inven-
tion and in what manner the same is to be performed, we declare that what we
claim is :-
1. A ball grinding machine characterised by by two polygonal sided rings a, b,
formed of a number of seginents, the opposite edges of which rings are oblique
and leave a space for the introduction of balls to be ground; by a rotary driving
ring C located underneath said space and by which the balls are pressed and carried
round against the polygonal groove formed by the rings a, b; and by a vertically
adjustable grinding ring or wheel mounted to rotate over the rings a, b, for grinding
the ball surfaces as they protrude from the polygonal groove, the balls being driven
by the ring C round horizontal axes which are caused by the polygonal edges of
the rings a, b, to vary their position so that the whole surface of the balls is
subjected to grinding action, substantially as described and shewn.
2. In a machine of the kind referred to, the provision of two ball holding rings
forming between them a circular ball holding groove for the reception of balls
to be ground one, a, of said rings being fixed, the other, b, with a projecting
portion on its oblique surface, adapted to be rotated in a direction contrary to
that of the driving wheel C, for the purpose specified, substantially as described
with reference to Figs. 1^, 2, 3, 4.
Dated this 29th day of October 1898
THOMAS R. SHILLITO,
15, Tooks Court, London, E.C., Agent for the Applicants.