Improved Ball Bearing Castor
Year: 1893

page_text: Date of Application, 21st Feb., 1893
Complete Specification Left, 10th Nov., 1893—Accepted. 16th Dec.. 1893
PROVISIONAL SPECIFICATION.
Improved Ball Bearing Castor.
ROBERT PARKER Cotton Waste Spinner Newhey near Rochdale Lancashire.
I do hereby declare the nature of this invention to be as follows:-
This invention relates to castors for furniture and other articles required to be
moved by a rolling action. And is performed in this manner. A ring of small balls
are placed between the plate or socket base which are fixed to the article to be
moved and another circular plate which carries the castor pulley. These balls are
enclosed by a flange on the upper plate or socket and roll in slightly hollowed
grooves in the upper and lower plates when the castor is swiveled. The castor
pulley being mounted on the lower circular plate directley under the ring of small
balls consequently the castor pulley is always central bearing and will swivel with
perfect case irrespective of added weight. To attach the parts I have a central
nipple on the lower plate fitting into a hole in the upper base or plate these are then
heald together by a screw through the hole in the upper plate screwed into the
Jower.
Dated thin 014 1
1000
ROBERT PARKER.
COMPLETE SPECIFICATION.
Improved Ball Bearing Castor.
I ROBERT PARKER Cotton Waste Spinner Newhey near Rochdale Lancashire
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 castors for furniture and other articles requiring to be
moved by a rolling action and in order that it may be better understood I refer to
the accompanying drawings.
Fig. 1 is a cross section of a castor constructed in accordance with my invention
the section being taken through the centre and parallel with the axis of the
roller.
Fig. 2 is a part cross-section taken at right angles to Fig. 1 and also showing
certain modifications.
A is a socket which may be attached to the leg B of any chair, table, piano, or
other article. It is constructed with a lower annular flange a within which is a
turned recess a¹ and within this is a central boss a' having a truly bored hole a³.
C is the roller plate carrying the roller D by the ordinary flanges c and the pivot
or shaft d. The periphery of the plate C is turned to a diameter slightly less than
the inside of the flange a and upon its upper surface a truly turned recess o¹ is
formed and centrally the boss or nipple is truly turned to fit the before-described
hole as in the boss a. Within the annular space thus left between the groove a¹
and the groove c' a ring of balls E is inserted. It will be observed that there is
clearance between the face of the boss a' and the upper surface of the plate c¹ and
also between the face of the boss c' and the bottom of the recess or hole a.
bold the plate C and the wheel A while allowing for their easy revolution the
central screw F is provided which in Figure 1 is shown as an ordinary V headed
screw in which form it is constructed so as to screw tight in the threads or to abut
against the bottom of its tapped hole as shown, slight clearance being allowed under
its head not however shown in the drawing. In the form of screw shown in Fig. 2
the shoulder is screwed down tight upon the upper face of the boss of while
Price 8d 1
To

page_text: clearance is allowed as shown under the head of the screw. By these means it is
impossible to jamb the balls by screwing the plate C tight against any portion of
the socket A. -
It will be observed in Fig. 2 that the vertical centre-line of the castor roller D falls
slightly within the vertical centre-line of the ball E. It may coincide with this centre-
line as described in my Provisional Specification but I may place the centre-line of
the roller D at any point between the centre-line of the socket and screw and the
position above described without departing from iny invention.
I make the attachment of the socket A in any suitable form as for instance a
plate as shown dotted at a' in Fig. 2.
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 :-
1. The ball bearing castor having the line of bearing of the castor pulley under
or within the line of bearing of the balls and combined with a central true fitting
nipple substantially as and for the purposes hereinbefore described and illustrated
in the accompanying drawings.
2. The ball bearing castor having the central true fitting nipple combined with
the central screw substantially as and for the purposes hereinbefore described and
illustrated in the accompanying drawings.
Dated this 9th day of November 1893
EDGAR CONISTON MILLS,
Agent to the Applicant.