IMPROVEMENTS IN CASTERS FOR FURNITURE ALSO APPLICABLE TO OTHER FRICTION REDUCING PURPOSES
Year: 1884

page_text: I ERNST PFEIFFER, of Queen Victoria Street, in the City of London, Merchant
do hereby declare the nature of the said Invention for "IMPROVEMENTS IN CASTERS
FOR FURNITURE ALSO APPLICABLE TO OTHER FRICTION REDUCING PURPOSES " to
be as follows:-
This Invention relates to the construction of an improved ball caster for
furniture of all kinds applicable also to gates, turntables and the like where it is
required to reduce friction between moving surfaces, the object of the Invention
being to provide a caster which shall have a very small amount of frictional or
rubbing surface.
In carrying out my Invention I provide a tubular socket or case in which I place
a loose ball of suitable material, the said ball forming the "roller" of the caster;
the opening at the bottom of the case or socket is formed with a lip or flange so
that the diameter of the opening is less than the diameter of the ball whereby the
latter is retained within but can partly protrude from the said socket or case.
Above the said ball or "roller" is a plate or its equivalent in the centre of which
is a recess of suitable shape and between the ball or roller and the said recess
I place a small ball of suitable material, so that when the caster is applied to an
article of furniture or otherwise used, the roller ball will bear against the
herein before described smaller ball, the points of contact between the ball and the
floor or surface on which the caster rests, between the two balls and between the
smaller ball and the recess in which it is placed, being the only frictional surfaces
in the caster.
The casters may be fixed to articles of furniture, safes, sewing machines,
turntables, gates and the like in any suitable manner such as by means of a socket,
a plate, or a screw.
Casters of this description when applied to articles of furniture or otherwise will
allow of the same being easily moved in any direction, the friction of the parts
being reduced to a minimum.

page_text: I ERNST PFEIFFER of Queen Victoria Street in the City of London, Merchant
do hereby declare the nature of my Invention for "IMPROVEMENTS IN CASTERS
FOR FURNITURE ALSO APPLICABLE TO OTHER FRICTION REDUCING PURPOSES
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 construction of an improved ball caster for
furniture of all kinds applicable also to gates, turntables and the like where it is
required to reduce friction between moving surfaces, the object of the Invention
being to provide a caster which shall have a very small amount of frictional or
rubbing surface.
In carrying out my Invention I provide a tubular socket or case in which I place
a loose ball of suitable material, the said ball forming the "roller" of the caster;
the opening at the bottom of the case or socket is formed with a lip or flange so
that the diameter of the opening is less than the diameter of the ball whereby the
latter is retained within but can partly protrude from the said socket or case.
Above the said ball or "roller" is a plate or its equivalent in the centre of which is
a recess of suitable shape and between the ball or roller and the said recess I place
a small ball of suitable material.
In order to enable my Invention to be fully understood I will proceed to describe
the same by reference to the accompanying Drawing in which Figure 1 is an
elevation and Figure 2 a vertical section of a caster constructed according to my
Invention the top of the caster being formed of a plate with a flange to allow it
to be screwed to the piece of furniture or the like; Figure 3 is a plan of the
underside of Figure 1, and Figure 4 a plan of the underside of the caster, the
"roller and small ball being removed; Figures 5 and 6 are similar views to
Figures 1 and 2 but showing the upper part of the caster formed into a socket;
Figure 7 is a vertical section of a caster having the socket or case formed in one
piece. Similar letters in all the Figures represent similar parts.
"
a, is the tubular socket or case which may be formed in two parts one screwing
into the other as shewn in Figures 1, 2, 5 and 6 or in one piece as shewn in
Figure 7; b, is the lip or flange at the opening at the bottom of the case or socket;
c, is the ball forming the "roller" the diameter of the said ball being somewhat
larger than the diameter of the opening at the bottom of the caster so that the
ball c, will be retained within but can partly protrude from the socket or case a, as
shewn; d, is the plate above the ball c, which plate may form one with the upper
part of the case or socket a, when the same is formed in two parts as in
Figures 1, 2, 5 and 6 or may be made separate and fixed in the case or socket a, as
shewn in Figure 7 by screws or equivalent means; e, is the recess in the centre of
the plate d, and f, is the small ball which is placed between the "roller" c, and
the said recess e; the said recess retains the ball f, in position and may be provided
with a loose piece of steel g, or the like forming a hard polished bearing surface
for the ball f.
If a caster of this construction is applied to an article of furniture or otherwise
used the roller ball c, will bear against the hercinbefore described smaller ball f,
the points of contact between the ball c, and the floor or surface on which the
caster rests between the two balls c, and f, and between the smaller ball f, and the
plate g, in the recess e, in which it is placed being the only frictional surfaces in
the caster.

page_text: The casters may be fixed to articles of furniture, safes, sewing machines,
turntables, gates and the like in any suitable manner such as by means of a plate d,
as shown in Figures 1 and 2, by means of a socket as shewn in Figures 5, 6 and 7
or by a screw.
Casters of this description when applied to articles of furniture or otherwise, will
allow of the same being easily moved in any direction, the friction of the parts
being reduced to a minimum.
Having now particularly described and ascertained the nature of my said
Invention and in what manner the same is to be performed I declare that what
I claim is :-
The improved caster hereinbefore described and represented in the accompanying
Drawing.