Improvements in Castors for Furniture.
Year: 1894

page_text: Date of Application, 28th July, 1894-Accepted, 1st Sept., 1894
VUMI DELE
Improvements in Castors for Furniture.
I, EDWARD PRATT, of 15s, Boulevard St. Denis, Paris, in the Republic of
France, Engineer, 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 and accompanying drawing, that is to say :-
My present invention relates to a novel form of castor for furniture, consisting
essentially of a ball of steel or other suitable material turning in a hemispherical
socket.
In the accompanying drawing, which is in illustration of my invention, the
improved castor is shewn applied in three different manners.
1st. The case in which the castor has to be fitted upon the bottom of an article
of furniture or on the lower flat end of a broad foot upon the latter.
2nd. The case in which a foot of small diameter is fitted into a socket upon the
castor, and
3rd. The case in which the upper part of the castor is fitted into a recess at the
bottom of the article of furniture or of a foot upon the latter.
Figure 1 is an elevation and Figure 2 a vertical section of a castor arranged to
be screwed to the bottom of the foot of an article of furniture, or to the bottom of
the latter itself.
This castor consists of a ball a of steel or other suitable material turning freely
in a socket b. The socket b together with the ball a is enclosed in a cylindrical
box c screwed at its lower outer edge so that a ring or cover d can be screwed upon
it, which holds the ball in its place whilst allowing it sufficient play, and provides
sufficient space between the bottom of the foot or of the furniture and the ground.
On the flat top of the cylindrical box c is a countersunk hole c for a screw by
which the castor is fixed in its place.
Figures 3 and 4 shew in elevation and in vertical section, a castor for the foot of
a table, chair, sofa, bedstead, or other article of furniture having wooden or
metal feet of small diameter which are fixed by means of screws or other
fastenings in the hollow cylinder e cast or stamped out of metal in the same piece as
the socket b.
The slightly conical ring and cover d is fitted upon the outside of the similarly
shaped part b, e. The object of the cover d is the same in the different forms of
castor.
Figure 5 shews in vertical section a form of castor serving the same purpose.
This form is obtained by the addition to that described and shewn in Figures 1
and 2, of a small projecting cylindrical ring c² formed upon the box c and
intended to receive the lower end of the foot of the furniture. The other parts
are the same.
Other modifications for the same purpose are shewn in half vertical section in
Figures 6 and 7. In Figure 6 the hollow conical socket e for the foot and the
hemispherical socket 6 for the ball are formed out of a single sheet of metal.
The ball a is kept in its place by a spherical ring d fixed upon the socket e
by screws.
Figure 7 shews a stronger and neater form of the castor shewn in Figures 3
and 4.
The socket e is cylindrical and is provided with holes for screws or rivets. The
cover d is screwed upon the lower end of the socket b.

page_text: The castor shewn in vertical semisection in Figure 8 is intended, like that shewn
in Figures 1 and 2, to be fixed below the foot, or upon the bottom, of an article of
furniture. The ball a is always the same. The hemispherical socket 6 is provided
with a vertical cylindrical ring f which carries round the whole of its upper
surface the lower side of the top of the box c, which is first fixed in position by
a screw in the manner already described. This arrangement presents considerable
resistance against breakage. The cover d, like that shewn in Figure 6 consists of
a cylindrical ring terminating below in a spherical ring.
.
Figure 9 is a vertical half section of a castor intended to be let into the lower
end of the foot of an article of furniture, or into a metal socket upon the furniture.
The part thus let in will be the socket b, as far down as the ledge formed round it
by the ring or cover d screwed upon its lower end.
The different forms of castor which I. have described possess in common an
important point in relation to the particular form of the socket b which receives
the ball.
The hollow part of this socket is slightly enlarged towards its edges so that the
ball will only be in constant contact with the bottom of the socket, and will not be
exposed to friction in the parts approaching its diameter.
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 combination of a ball turning freely in every direction in a hemispherical
socket fitted in a support of suitable construction, the said support being fixed
under the article of furniture to which it is to be applied, in the manners
described, and replacing the castors ordinarily used, substantially as described and
illustrated.
2. The method of construction and application of the ring or cover d which
keeps the ball in its place and prevents it from coming out of the socket in which it
turns, whilst leaving the necessary room for its free rotation, and which preserves
the necessary distance between the support which contains the ball and the floor,
substantially as described and illustrated.
3. The method of enlarging the socket b so as to prevent lateral friction against
the ball a.
4. The form of the socket 6 shewn in Figure 8, with an upward projecting ring f
which supports the lower side of the top of the box c round its whole circumference,
and at its centre by the head of the screw by which the castor is fixed, substantially
as described and illustrated.
5. The different forms of support described, and the method of applying them to
different articles of furniture, or parts of such furniture, substantially as and for
the purpose described and illustrated.
Dated this 27th day of July 1894.
EDWARDS & Co.,
65 and 66, Chancery Lane, London, Agents for the Applicant.