CERTAIN IMPROVEMENTS IN CASTORS
Year: 1856

page_text: LETTERS PATENT to Thomas Bird, of Manchester, in the County of Lan-
caster, Engineer, and Thomas Rose, of the same Place, Engineer, for the.
Invention of "CERTAIN IMPROVEMENTS IN CASTORS."
Sealed the 15th July 1856, and dated the 18th March 1856.
PROVISIONAL SPECIFICATION left by the said Thomas Bird and Thomas
Rose at the Office of the Commissioners of Patents, with their Petition,
on the 18th March 1856.
We, THOMAS BIRD, of Manchester, in the County of Lancaster, Engineer,
and THOMAS ROSE, of the same Place, Engineer, do hereby declare the nature
of our said Invention for CERTAIN IMPROVEMENTS IN CASTORS, to be as follows:-
Our Invention consists in the novel and peculiar application of a ball or
sphere to the extremities of the legs of furniture or other heavy bodies to act
as "castors." A ball or sphere of metal, glass, porcelain, or other suitable
substance is placed in and underneath a metal cup or retainer, the top of the
interior of which is formed in such a manner as to present a convex surface or
conical point to the top or upper surface of the ball, and also so that the sides
of the cup shall present a projecting rim at a point about one-third of the
diameter measuring from the top of the ball downwards; by this arrangement
one-third of the diameter of the ball being above the rim, and two-thirds below,

page_text: a great leverage is obtained, thereby facilitating the universal revolution of the
ball, consequently, the lateral movement of the furniture; the ball must be
slightly less than the rim bearing against it, so that the upper conical point or
centre of downward pressure may not come directly over the centre of lateral
motion. By this arrangement, the ball (when revolving) will bear between
the upper conical point and that side of the rim from whence the motion is
given; this may also be effected by cutting away part of the sides of the cup,
leaving only three prongs or claws to confine the ball in order to produce less
friction. We propose to form a hollow in the conical point, and each of the
bearing points, or the prongs or claws for the reception of a smaller ball of
metal or stone, &c., as a substitution of the fixed bearing or touching points,
&c., upon which the large ball will then bear. The ball is retained in the cup
by means of a circular cap fitting on to the ends of the claws, and having a
hole formed in it rather less than the diameter of the ball through which the
ball will extend and roll acting as "castors."
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Thomas Bird and Thomas Rose in the Great Seal Patent
Office on the 17th September 1856.
TO ALL TO WHOM THESE PRESENTS SHALL COME, wе, THOMAS
BIRD, of Manchester, in the County of Lancaster, Engineer, and THOMAS
ROSE, of the same Place, Engineer, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Royal
Letters Patent, bearing date the Eighteenth day of March, in, the year of our
Lord One thousand eight hundred and fifty-six, 'in the nineteenth year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto us, the
said Thomas Bird and Thomas Rose, Her special licence that we, the said
Thomas Bird and Thomas 'Rose, our executors, administrators, and assigns, or
such others as we, the said Thomas Bird and Thomas Rose, our executors,
adininistrators; and assigns, should at any time agree with, and' no others,
from time to time and at all times thereafter during the term therein
expressed; should and lawfully might make, use, exercise, and vend,..within
the United Kingdom of Great Britain and Ireland, the Channel Islands,
and Isle of Man, an Invention' for: "CERTAIN IMPROVEMENTS IN CASTORS,"
upon the 'condition (amongst others) that we, the said; Thomas Bird and
Thomas Rose, by an instrument in writing under our hands and seals, or
under the land and seal of one of us, 'should' particularly describe and' ascer-

page_text: tain the nature of the said Invention, and in what manner the same was to
be performed, and cause the same to be filed in the Great Seal Patent Office
within six calendar months next and immediately after the date of the said
Royal Letters Patent.
NOW KNOW YE, that I, the said Thomas Bird, for and on behalf of
myself and the said Thomas Rose, do hereby declare the nature of the said
Invention, and in what manner the same is to be performed, to be par-
ticularly described and ascertained in and by the following statement (that
is to say) :-
Our Invention consists in making the lower or rolling part of castors in the
form of spheres, globes or balls, of any convenient dimensions, having their
upper parts pressing against one or more smaller balls or spheres, the whole
being enclosed in suitable standards or frames, either with or without anti-
friction rollers, pulleys, or balls. The frame of the castor is provided with a
screw, in order to lengthen or shorten it, when required, to adjust the article
of furniture to a proper height, and if the surface of the floor is uneven, to
adjust it to the various inequalities, and give it a perfect-level, which arrange-
ment will be found peculiarly applicable to pianos and similar articles...
These improvements will be clearly understood by reference to the accom-
panying Sheet of Drawings, and the letters of reference thereon, which refer
to similar parts in all the Figures.
Fig. 1 is an external elevation, and Fig. 2a sectional elevation of a large
castor, having a propelling edge or rim without antifriction pullies or rollers;
Fig. 3, an external elevation of a castor with antifriction propelling pullies,
instead of the propelling edge or rim; Fig. 4. is a sectional elevation of a
castor with antifriction pullies, shewing another mode of attachment' to the
article for which it is required; Fig. 5 is a plan of a castor in which balls
or spheres are employed, instead of antifriction pullies or rollers.
In Figs. 1 and 2, the frame of the castor consists of three parts a, b, and c,
united by the external, and internal screws d and e, the part c being the
keeper. The sphere or roller is, shewn at f, being a little smaller at one-.
third of the diameter from the top than the propelling edge g of the frame,
to allow freedom of action for moving in any direction; the upper part of the
sphere or ball plays against a smaller sphere or globe h, placed within the
cup i, having a pointed or spherical surface k, which is made of glass, steel,
patent metal, or other hard material, which forms a fulcrum at about the
centre. The sphere or ball h fits loosely within its cup i, so that it may be
able to move in any direction, or a fast or loose convex centre may be substituted
for it.

page_text: In Figs. 3 and 4, the lower ball or sphere is bounded at the sides by anti-
friction propelling rollers or pullies 1, any convenient number of which may be
used; but it must be observed that the said antifriction rollers or propelling:
pullies have no weight whatever to sustain, the whole weight resting, vertically
on the bottom sphere and centre point, leaving the propelling edges and pro-
pelling balls or pullies perfectly free from any weight or resistance. When
desired, we attach to the article a castor, having an adjusting screw, either
with or without a set nut in the frame of the castor for raising or lowering the;
article on which it is fixed, as shewn at Figs. 1 and 2. This castor, with
the screw, is for the purpose of adjusting the article to the exact height required,
and fixing it to a perfect level, which is often very difficult, on account of
inequalities in the surface of the floor.
In our improved castor, we make the large sphere or ball of glass, and the
small one of ivory, or similar material, thus making it a double spherical in-
sulator peculiarly applicable to pianos, harps, or other musical instruments.
When force is applied to the article to which the castor is attached, a reaction
commences at m, which may be considered as the moving power of a lever
shewn by the dotted line n, having its fulcrum at o, about two-thirds of the
diameter of the lower ball. The fulcrum o becomes the moving power of a
shorter lever, shewn by the dotted line p, representing the other third of the
diameter of the lower ball; the upper part p then becomes the moving power,
which acts upon the smaller sphere or globe h, causing it to move, oscillate, or
rotate in its cup with endless changes of position, and allows the lower sphere
to roll in any direction with ease and steadiness, the said spheres being made
of glass, iron, brass, wood, or other suitable metal or composition, and are
admirably adapted for gun carriages, signal posts, turn tables, safes, sofas,
pianos, harps, or any kind of furniture or article requiring to be moved about.
Instead of the one smaller ball h in the cup i, any desired number may be
used; and also, instead of antifriction propelling pullies, we may employ
balls or spheres placed in suitable cups or holders, as shewn in Fig. 5.
When desired, any of the cups for holding the spheres or balls may be
bounded by india-rubber or spring 9 (see Fig. 2) or other material, in order
to prevent noise.
Having thus fully described the nature and particulars of our said Invention,
and the manner of carrying the same into practical effect, we desire it to be
distinctly understood that we do not confine ourselves to the exact details
herein set forth, as such may be varied or modified without departing from the
principle thereof; but we claim as our Invention, and which to the best of our
knowledge and belief has not been hitherto used within this realm, the con

page_text: ruction of castors with one or more spheres or balls, placed in a cup and
orking loosely against one or more points, spheres, or balls, in conjunction
ith a larger ball, with its propelling rim composed of balls, pullies, or edges,
s herein described, and illustrated in the accompanying Sheet of Drawings.
In witness whereof, I, the said Thomas Bird, for and on behalf of myself
and the said Thomas Rose, have hereunto set my hand and seal, this
Sixth day of September, One thousand eight hundred and fifty-six.
THOMAS BIRD. (L.S.)
Signed, sealed, and delivered by the within-named
Thomas Bird, in the presence of
E. J. HUGHES, Patent Agent,
Manchester.