Poved at bearing Castor.
Year: 1898

page_text: Date of Application, 20th Dec., 1898-Accepted, 28th Jan., 1899
DE Poved at bearing Castor.
I, EDWARD LOWRY DIMMITT, of 318, Park Avenue Street, in the City of Kansas,
in the County of Jackson and State of Missouri, United States of America,
Banker, 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 improvements in ball bearing castors.
The object of my invention is to provide a castor that may be used on the legs of
chairs, tables and other furniture. My invention is also applicable to trunks, chests,
skates and in fict almost all articles requiring a rolling support.
My invention provides a castor that is cheap in construction, easily applied and
operates with a minimum of friction.
My invention provides further certain new and useful features of construction
hereinafter fully described.
In the accompanying drawings which illustrate my invention, Fig. 1 represents a
side elevation view. Fig. II represents a vertical sectional view. Fig. III represents
a plan view, and Fig. IV represents a horizontal sectional view taken on the dotted
line a-b of Fig. II. Fig. V represents a vertical sectional view of the lower part of
a castor in which the ball holder is composed of a single piece, and in which the cup
D is dispensed with. Fig. VI represents a modification of any invention applied to
a skate.
Similar letters of reference indicate similar parts.
A indicates the ball holder, the lower end of which is provided with a semi-spherical
shaped opening in which is placed the roller ball B which is held in place by means
of a ring C which is contracted at its lower end to prevent the ball falling out and has
a screw threaded connection with the lower end of the part A. Within the holder A
above the ball B is a ball E around which are grouped several balls F. The disposition
of the balls E and F is such that the roller ball B will have a bearing upon all of
them. If desired the balls E and F may be mounted in a hardened steel cup D
fitted to the interior of the recess in the holder A. The holder A is provided with a
central upwardly extending shank G fitted rotatably in a sleeve H which is provided
at its upper end with an annular or other shaped depression I which is adapted to
enter a recess J on the periphery of the shank (F. This arrangement permits relative
rotation of the parts without allowing them to become detached.
At the lower end of the sleeve H is provided a horizontal plate or disk K having
suitable openings therethrough for the insertion of screws L used to secure the castor
to the table or chair leg. Around the shank G and between the disk K and the
upper end of the holder A are grouped a series of balls M. To prevent wear upon the
parts the balls M may be placed in hardened cups M and O respectively. These cups
are each provided with a central opening for the passage of the shank G, the cup N
being located inverted against the plate K, and the cup 0 in a
recess in the
apper end of the holder A. In the modification shown in Fig. V the cups D,
N and O are dispensed with. Such a construction may be utilized where the
castor is little used, but in cases of much wear the cups should be eniployed
to prevent undue wear. In the modification just referred to the ring C and the
7.

page_text: body of the holder A are integral, the lower end of the holder being inwardly
turned after the balls E, F and B have been placed therein. In Fig. VI is
shown a skate provided with two of my castors. When so used the shank G and
sleeve E are made much shorter than where the castors are used on tables or
chairs. In the drawing but two castors are shown applied to the skate platform P,
one under the ball of the foot and one under the heel. More may be used and they
may be applied in either an inclined or a perpendicular position.
In applying my invention, the chair or table leg is first provided with a vertical
hole to receive the sleeve H, after which it is secured by means of screws L
passed through the disk K. The shank G is then inserted into the sleeve, the
balls E, F, B and M having been placed in their proper places as well as the
cups D N and O. The depression I of the sleeve engaging with the shank prevents
the displacement of the parts after insertion of the shank into the sleeve. When the
castor is inclined sidewise, the balls M provide a double bearing for the sbank and
prevents its cramping in the sleeve. If for any reason the ball B becomes tight in
its seat, the balls M provide a non friction bearing for the upper end of the holder
and permits its rotation with small friction.
My invention may be applied to many different articles and subjected to many
modifications without departing from the spirit of my invention.
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
Claim 1. In a castor the combination with a holder provided with an upwardly
extending shank and a recess in its lower end, of an inverted cup, in the said recess,
one or more balls located in the said cup, a roller ball located in the said recess and
bearing upon the said balls in the eup, means for preventing the falling out of the
roller ball from the recess, a cup upon the upper end of the holder provided with a
hole through which the shank extends, a series of balls located in the said cup, an
inverted cup upon the said series of balls, and a sleeve provided with means for
securing to the article on which the castor is to be used and adapted to receive
therein the shank, substantially as described.
2. In a castor, the combination with the holder provided with an upwardly
extending shank and a recess in the lower end, of a seat in said recess, a series
of balls in said seat, a roller ball located in said recess, a ring the upper end of
which is secured to the lower end of the holder, the ring being smaller in its
smallest internal diameter than the diameter of the roller ball, a sleeve provided
with a disk at its lower end having an opening adapted to receive the shank,
means for detachably securing the shank to the sleeve while permitting its rotation
therein, and a series of balls upon the holder and grouped around the shank and
adapted to support the disk when the shank is inserted into the sleeve, substantially
as described.
EDWARD LOWRY DIMMITT.
Haseltine, Lake & Co.,
45, Southampton Buildings, London, W.C., Agents for the Applicant.