Year: 1887

page_text: Date of Application, 20th Sept., 1887
Complete Left, 20th June, 1888
Complete Accepted, 20th July, 1888
Wo ISAAC CHORLTON of Blackfriars Street Manchester in the County of Lancaster
Spring Mattress Manufacturer and GEORGE LAMB SCOTT also of Manchester aforesaid
Engineer do hereby declare the nature of this Invention to be as follows:-
Our said Invention relates to castors for application to beds and bedsteads, couches,
chairs and other articles of Furniture. According to our invention we provide the
bowls of such castors with rubber tyres or treads which are inserted or spring into
The said
grooves or recesses turned or formed in the peripheries of the bowls.
grooves or recesses are formed with undercut or overhanging sides which embrace
and hold the rubber and prevent it from becoming loose. The tread or periphery
of the tyre is preferably of a curved or circular section and a convenient section of
tyre is a ring of round rubber sprung into a circular recess turned in the bowl to
receive it. The ring is embedded in the bowl so as to present about one third of
its circumference above the level of the bowl periphery, the groove to receive it
thus overhanging the embedded portion of the ring, so as to hold it in place. We
may however form the ring tyre of any suitable section so long as it is held in
position in the bowl by means of an undercut, dove-tail or other recess having
overhanging sides which will hold it firmly so as to prevent it from being pulled
or twisted out by the gyratory movements of the pivotted portion or bracket of
the castor. Our present invention may be applied to all types of castors and may
be used in conjunction with the improved castor for which we have obtained Her
Majesty's Letters Patent No. 9718 of the year 1886. Castors provided with
our improved rubber tyres or rings are applicable to furniture generally and
in particular to Hospital or Invalid Beds, Couches and chairs in which an elastic,
soft and noiseless contact with the floor is desirable.
Dated this 10th day of September 1887.
DUTTON & FULTON,
1, St. James Square, Manchester,
Agents.

page_text: COMPLETE SPECIFICATION.
Improvements in Furniture Castors.
We ISAAC CHORLTON of 19 Blackfriars Street, Manchester in the County of
Lancaster Spring Mattress Manufacturer, and GEORGE LAMB SCOTT, also of
Manchester aforesaid, 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 drawings :-
Our said Invention relates to castors for application to beds and bedsteads, couches,
chairs and other articles of furniture. According to our Invention we provide the
bowls of such castors with rubber tyres or treads which are inserted or sprung into
grooves or recesses turned or formed in the peripheries of the bowls. The said
grooves or recesses are formed with undercut or overhanging sides which embrace and
hold the rubber and prevent it from becoming loose. The tread or periphery of the
tyre is preferably of a curved or circular section and a convenient section of tyre is a
ring of round rubber sprung into a circular recess turned in the bowl to receive it.
The ring is embedded in the bowl so as to present about one third of its circumference
above the level of the bowl periphery, the groove to receive it thus overhanging the
embedded portion of the ring so as to hold it in place. We may however form the
ring tyre of any suitable section so long as it is held in position in the bowl by means
of an undercut dove-tail or other recess having overhanging sides which will hold it
firmly so as to prevent it from being pulled or twisted out by the gyratory movements
of the pivotted portion or bracket of the castor.
And in order that our said invention may be properly understood we will now
proceed more particularly to describe the same with reference to the annexed sheet of
drawings.
Fig. 1 of the said drawings is a cross section of a castor bowl fitted with a rubber
ring in accordance with our invention. Fig. 2 is a side view of the bowl. The body
of the bowl a is made of metal or hard wood or other suitable substance or material
and has a groove cast, turned or otherwise formed in its periphery of the shape clearly
indicated in Fig. 1. It will be seen that the upper part of the groove overhangs the
lower part so as to hold securely a rubber ring which is sprung into the groove and
which should present about one third of its bulk above the periphery of the bowl. We
prefer to make this rubber ring of a circular section as shown, and to form the groove
of a corresponding shape, this being what we consider the cheapest and most con-
venient mode of carrying our invention into effect, but we do not confine ourselves to
this. When the bowl is placed in a castor and is in use, the projecting portion of the
rubber bears upon the floor and either sustains the bowl clear of the floor or softens
the contact of the bowl with the floor. When the bowl is made of metal or of a
substance capable of withstanding heat we vulcanise the rubber in position and so
cause it to adhere to the bowl, or we might in some cases cement it in the groove.
These methods of securing the ring, together with the effect of the overhanging sides
of the groove, hold the rubber securely and prevent it from being twisted out of the
groove by the gyratory movements of the pivotted portion or bracket of the castor.

page_text: Fig. 3 is a cross section and Fig. 4 a side view of a castor bowl fitted with a rubber
ring of a section different from that shown in the preceding figures. In this instance
the rubber ring c is double headed in section and occupies a groove of a corresponding
shape. In Figs. 5 and 6 the rubber ring d is half round on the top and is dovetailed
into the bowl. In Fig. 7 a rubber ring e of triangular section is dovetailed into the
bowl. It will be obvious that other sections of rubber ring might be employed so
long as they are placed or sprung into correspondingly shaped grooves with over-
hanging sides formed in the periphery of the bowl.
The invention may be applied to all types of castors and may be used in conjunction
with the improved castor for which we have obtained Her Majesty's Letters Patent
No. 9718 of the year 1886. Castors provided with our improved rubber tyres or
rings are applicable to furniture generally and in particular to hospital or invalid beds,
couches and chairs in which an elastic, soft and noiseless contact with the floor is
desirable.
Having now particularly described and ascertained the nature of our said
invention and in what manner the same is to be performed we declare that what
we claim is :-
In furniture castors forming the bowl with a circular or other suitably formed
undercut groove in its periphery and placing or springing a rubber ring of a round or
other suitable or corresponding section in the said groove the rubber projecting or
standing above the level of the periphery of the bowl so as to form an elastic and
noiseless tread substantially as herein before described and shown.
Dated this 19th day of June 1888.
DUTTON & FULTON,
1, St. James Square, Manchester,
Agents.