Improvements relating to Furniture Castors.
Year: 1895

page_text: Date of Application, 26th Nov., 1895-Accepted, 6th June, 1896
T
COMPLETE SPECIFICATION.
Improvements relating to Furniture Castors.
1 JOHN ALEXANDER KENNEET MCGREGOR of 20' Gillingham Street in
County of London, Electrical 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 :-
This invention relates to the manufacture of furniture castors of various kinds,
and consists in the manner of constructing the various parts, whereby simplicity,
economy, and efficiency are obtained.
In the accompanying drawings:
T
:―
County of London, Electrical 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 :-
This invention relates to the manufacture of furniture castors of various kinds,
and consists in the manner of constructing the various parts, whereby simplicity,
economy, and efficiency are obtained.
In the accompanying drawings
:-
Fig. 1, Sheet I, is a front view of one form of castor, with certain of my impro
ments adapted thereto;
Fig. 2 being a side view, with one wheel or roller of a pair removed.
Fig. 3 and 4 are similar views of a slight modifications
.
Figs. 5 and 5 represent the two parts of a socket for the pivot pin, 'in
juxtaposition.
Fig. 6 shows the parts brought together.
Fig. 7 is a section taken at right angles to Fig. 6;—and
Fig. 8 is a cross section of the same figure.
:
Fig. 9 is a sectional view, on an enlarged scale, showing how the two parts are
secured together.
Figs. 10 to 13, Sheet II, show the various operations in the construction of a
socket for a socket castor, according to my invention; and
Figs. 14 to 17, Sheet I, and Figs. 18 to 24, Sheet II, show the various operations
in the construction of wheels for castors, according to my invention.
Referring now to Figs. 1 to 4, which relate to what are known as pin castors,
A is a cylindrical pin, and B the pin sccket, which is let into the piece of furniture,
say, the leg of a table. The pin A. rotates in the socket B, and is held therein by
a spring piece a', stamped out of the socket, which enters a groove b* near the end
of the pin.
This form of pin and socket is now well known. T.
According to my invention, the upper part, A, of the pin is round as before, but
the lower part, A', is flattened by being struck between dies. The pin is also at
this part bent at an angle, as seen in Fig. 2, in order to get the rake required to
cause the swivelling of the pin. The flattening of this pin gives great strength at
the bend, and also provides space for a hole, to receive the axle of a pair of wheels
or rollers.
It may be here remarked that I am aware a bent pin working in a socket has
been already proposed, but such pin did not itself carry the axle of the rollers; it
entered, and was pinned to, a separate socket, which formed the hearings for the
axle.
In Figs. 3 and 4, the same form of castor is shown, but the pin is combined with
a stamped bridge or horn A², which serves to support the outer ends of the
wheel axle, the flattening of the pin forming a shoulder at the junction between
the flattened and round portions of the pin, against which the horn rests.
The end of the pin A bears against, and turns on the end of the socket B,

page_text: which is thus liable to wear away, and I therefore propose to strengthen the end of
the socket as hereinafter described.
The socket B is also liable to work loose in the leg of the table, and to fall
out, and part of my invention is designed to prevent this. Further, I secure
the mouth of the socket in such a manner, that by no possible chance can the
mouth spread and break away the wood of the leg of the piece of furniture, under
the strain of the working.
To carry out my invention, so far as above indicated, I stamp out the socket B
in two parts from sheet metal, each part consisting of a semi-tubular portion a,
with a flange b at each side, and a triangular extension c of each flange at the
end. The parts a are slightly longer than the parts b, as seen in Fig. 5, and
in one of the parts a the retaining spring a¹ is formed.
When the two portions a b c are put together, to form the socket B, the
parts are first firmly secured together by a rivet, or in any other convenient
manner. The plate or collar d (of the form shown in Fig. 5A) is next placed
upon the extending portion of a, and then, by the blow of a suitably formed
punch, the part a is caused to curl round, and take under, or interlock with,
the curled over part of the plate d, as will be clearly seen in the enlarged view,
Fig. 9.
In adapting the socket to the article of furniture, a hole is first bored in the
article, the size and length of the tubular portion a of the socket, and the socket is
then driven in.
The triangular extension c cuts its way in the wood, and forms the paths
for the flanges b, which become firmly fixed in the grooves thus formed, so that the
socket B cannot turn round in the hole, nor move in any direction. The triangular
end c also forces its way into the solid wood at the end of the hole, and should the
end of the tube become worn away, will always present a metal bearing surface to
the end of the pin.
The plate or collar d may be formed with points e (see Fig. 9), to enter the end
of the leg, or the wood of the article of furniture, and, if necessary, the plate & may
be secured by two or more screws to the furniture.
In manufacturing sockets for socket castors, I take a length of brass tube of the
average diameter of the socket to be produced. This piece of tube I subject to
the action of a pair of dies, by which the lower half is contracted, and the upper
half expanded, to bring it to the necessary conical form.
At the same time a flange is turned inwards at the smaller end of the socket, and
a bead is formed at the top end.
The body of the socket thus produced is now ready to receive the bottom or end,
which is secured in a manner somewhat similar to that described for the pin socket,
that is to say; I take a disc of steel (preferably), and I so form it as to present a
flange at the back, which is placed inside the flange of the socket, and, by means of
a suitable die, the disc flange is turned back onto, and grips firmly the socket flange
all round.
In Sheet III have shown the various operations by which a socket is obtained;
thus, Fig. 10 shows the piece of tube inserted in the die, ready to be shaped for the
body of the socket ;
Fig. 11 shows the shaped socket body in section.
Fig. 12 shows, in section, the shaped socket body with the steel flanged bottom
in position; and
Fig. 13 shews, in section, the completed socket.
In producing wheels for castors according to this invention, I proceed in the
following manner, reference being had to Sheet 1 (Figs. 14, 15, 16 and 17) of the
accompanying drawings; thus, I first form from a disc (say) of brass, a cup having
a U-shaped annular recess, and a bulged portion in the bottom (see Fig. 14) I next,
by means of a suitable tool, slightly curl inwards the inner and shorter leg of the U,
as seen in Fig. 15. then take another disc, say, of steel, and I treat it in the
same way, so as to form a cup of slightly less diameter than the first; I next take

page_text: discs of steel, which I form to the saucer shape shown at f, f, and a flat disc g (see
Fig. 16), and place them inside the steel cup, and I place this steel cup in an
inverted position inside the brass cup, and subject both to slight pressure, so as to
cause the open ends of the cups to curl slightly round the steel cup inside and the
brass cup outside, as shown at Fig. 16. I next place a thin brass saucer-shaped
piece outside the bottom of the steel cup, and submit the whole to considerable
pressure, whereby the steel cup is caused to curl quite round inside the U portion
of the brass cup, and the brass cup is caused to curl completely round outside
the portion of the steel cup, and to firmly grip the thin brass saucer in position,
and clamp the parts together, all as shown in Fig. 17.
In this way I form a strong, cheap, and light (apparently brass) wheel from
comparatively thin metal.
It will be obvious that, if desired, I may make the wheel entirely of brass, or
entirely of steel, which may be brouzed, plated, or otherwise coated, to prevent
oxidation.
In place of manufacturing the wheel as above described, I may proceed in the
following manner, reference being had to Sheet II of the drawings; thus, I take
a sheet of metal, and stamp out blanks of the form shown at Fig. 18, that is to
say, a central disc portion with radial arms.
I then subject these blanks to treatment in a die, by which the radial arms are
turned up, and the central boss or bulge is formed, as shown at Figs. 19, 20.
I next take saucer-shaped and flat dises, as before described, and place them
inside one of the formed parts, and I place another formed part over them, so that
the arms of one part will interlock with the arms of the other, and extend beyond
the respective bulged portions, as shown in Fig. 21.
I then subject the parts thus assembled, to pressure in suitable dies, whereby the
extending portion of each arm is curled over, and caused to grip against the bottom
of the opposite part, as shown in Fig. 22.
I then take the wheel thus formed, and place it inside a piece of brass tube C,
with thin brass discs h on each face, as before mentioned (see Fig. 23), and, by
suitable dies, I cause the ends of the brass tube to curl inwards, as described in the
Complete Specification of my Application for Patent dated May 22nd 1895,
No. 10,127, so as to grip the brass discs against the steel lining, and produce what,
to all appearance, is a brass wheel, but which will have enormous strength, by
reason of the interlocking steel lining, as shown in Fig. 24.
It will be obvious that a strong wheel would also be made, if the material
employed were all brass.
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. A pin for pin castors having a cylindrical socket portion and a flattened bent
portion, to receive the axle of a pair of running wheels, as and for the purpose set
forth.
2. A socket for a pin castor, as herein shown and described, consisting of two
parts, each having a semi-tubular portion, an external flange on either side, and a
triangular-shaped prolongation, the two parts being rivetted or otherwise secured
together at the end, the mouth of the tubular portion being secured by an
overbanging flanged annular plate, with which the tubular portion is caused to
interlock, as shown and described.
3. The production of sockets for socket castors as herein shown and described,
that is to say, coning a piece of tube, and producing, at the same time, an inward
flange at bottom, and a bead at top, and adapting to the bottom a flanged end piece,
the flange of which is caused to curl outwards and grip or interlock with the socket
flange, as set forth.
4. Producing wheels for castors as shown and described with reference to
Figs. 14 to 17, Sheet I, of the drawings.

page_text: 5. Producing wheels for castors as shown and described with reference to
Figs. 18 to 24, Sheet II, of the drawings.
Dated this 25th day of November 1895.
NEWTON & SON,
Agents for the Applicant.