Improvements in Ball Bearings for Crank Shafts of Sewing Machines.
Year: 1899

page_text: PROVISIONAL SPECIFICATION.
Improvements in Ball Bearings for Crank Shafts of Sewing Machines.
I, JOHN KING MACDONALD, Manager of The Singer Manufacturing Company,
Kilbowie, Dumbartonshire, do hereby declare the nature of this invention (as
communicated to me by the Singer Manufacturing Company, of New York,
United States of America, Sewing Machine Manufacturers,) to be as follows:-
This invention has for its object to provide easy running bearings for the crank
shafts of sewing machines and to that end it consists of an improved construction
of ball bearings fitted in the machine stand to replace the ordinary cones or
journals in which the ends of the crank shaft rotate.
In carrying out the invention the crank shaft is made with tapered conoidal
ends or is fitted with removable end pieces of conoidal form and the bearings in
which the shaft ends are fitted to run are each formed by a cup, secured in a socket
or orifice in the machine stand or frame, and serving as a ball race wherein a
number of balls are fitted to bear on the conical part of the end of the shaft.
The balls are retained in place by a cover through an orifice in which the end
of the shaft passes into the cup.
Either or both of the cups which form the ball races may be adjustable to
permit of removing the shaft and renewal of worn parts, the outer periphery of
the cup piece being preferably screw threaded and the orifice in which the cup
piece is fitted being internally screw threaded to permit of such adjustment.
Dated this 1st day of Inil 1900
WALLACE FAIRWEATHER,
Of the Firm of Cruikshank & Fairweather,
Chartered Patent Agents. 62, Saint Vincent Street, Glasgow,
Agent for the Applicant.
I, JOHN KING MACDONALD, Manager of The Singer Manufacturing Company,
Kilbowie, Dumbartonshire, do hereby declare the nature of this invention and
in what manner the same is to be performed as communicated to me, to be
particularly described and ascertained in and by the following statement:-
This invention has for its object to provide easy running bearings for the crank
shafts of sewing machines and to that end it consists of an improved construction
of ball bearings fitted in the machine stand to replace the ordinary cones or
journals in which the ends of the crank shaft rotate.

page_text: The invention is illustrated by the accompanying drawings, Figure 1 being a
front elevation of part of a sewing machine stand or frame showing the improved
bearings in section, and Figure 2 is an end elevation of the same.
In carrying out the invention the crank shaft A is made with tapered or conoidal
ends A or is fitted with removable end pieces of conoidal form and the bearings
in which the shaft ends A' are fitted to run are each formed by a cup B, B,
secured in a socket or orifice C in the machine stand or frame C, and serving as
a ball race wherein a number of balls D are fitted to bear on the conical part of
the end A' of the shaft A. The balls D are retained in place by a cover or
washer E for each cup and which is crowned as shown at Figure 3, let into a dove-
tailed check in the cup B or B, and flattened, thus forcing the metal into the
dove-tailed check. Through orifices in these covers the ends A of the shaft A
pass.
Either or both of the cups B, B1, which form the ball races may be adjustable
(the cup B only being shown on the drawing) to permit of removing the
shaft A and renewal of worn parts, the outer periphery of the cup piece B¹ being
preferably screw threaded and the orifice C in which the cup piece B₁ is fitted being
internally screw threaded to permit of such adjustment. A pinching screw F is
provided for the purpose of fixing the adjusted bearing in position, and preventing
its rotation with the shaft A by friction.
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
1. The improved ball bearings for crank shafts of sewing machines constructed
and arranged substantially as described.
2. In sewing machines the combination of a crank shaft having conoidal ends
and ball bearings consisting of cups fitted in sockets in the machine frame each
cup being adapted to receive a number of balls which are retained therein by a
cover or washer let into the cup and through an orifice in which the end of the
crank shaft passes, either or both bearings being fitted adjustably in screw threaded
sockets substantially as described with reference to the drawings annexed.
Dated this 2nd day of January 1890
WALLACE FAIRWEATHER,
Of the Firm of Cruikshank & Fairweather,
Chartered Patent Agents. 62, Saint Vincent Street, Glasgow,
Agent for the Applicant.