Improvements in Metallic Packings.
Year: 1896

page_text: Date of Application, 15th May, 1896
Complete Specification Left, 29th July, 1896-Accepted, 12th Sept., 1896
PROVISIONAL SPECIFICATION.
Improvements in Metallic Packings.
I, WILLIAM AMBROSE BENNETT of 14, Suffolk Street, Poplar, London, E.
Marine Engineer, do hereby declare the nature of this invention to be as
follows:-
This invention relates to an improved metallic piston-rod packing and it has for
its special object to avoid undue wear of the packing by the lateral pressure of
the piston rod.
The packing is formed of white metal rings through which the piston rod passes
and which are fitted whole or in segments into an enclosing cylinder which is free
to move laterally in any direction within an outer casing, the inner cylinder being
incapable of end play yet floating freely between the ends of the outer casing and
yielding to any lateral pressure of the piston rod. Both portions may be divided
longitudinally into halves so as to admit of insertion in the stuffing box without
drawing the rod, the outer casing forming a lining for the stuffing box and acting
as a distance piece to prevent the pressure of the gland being transmitted to the
floating packing, the outer end cover being retained in position by set screws
engaging with its grooved periphery and forming the bottom of the space into
which a soft packing is compressed by the usual gland.
Dated this 15th day of May 1896.
A. M. & WM. CLARK,
53, Chancery Lane, London, Chartered Patent Agents.
1, WILLIAM AMBROSE BENNETT of 14, Suffolk Street, Poplar, London, E.
Marine 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 an improved metallic packing for piston and other rods,
and it has for its special object to avoid wear of the packing consequent on undue
lateral pressure of the rod caused by the oscillation of the rod during its stroke
(being permitted by play in the neck bush) and by the effect of expansion with
heat between the guide faces of the engine.
The improved packing will be described with reference to the accompanying
drawing forming part of this specification wherein the packing is illustrated in
longitudinal section in Figure 1, Figure 2 being a cross-section on line 2-2
Figure 1.
Similar reference letters denote similar parts in both figures.
The packing is formed of juxtaposed rings A of white metal fitting closely
around the piston: or other rod B and contained within a cylindrical casing C which
is fitted loosely within an outer casing (formed by a liner D and end plates E E!
contained in the stuffing box F) in such manner as to float freely between the end

page_text: plates E F and yield to lateral pressure of the rod in any direction whilst
maintaining a steam-tight joint.
The packing rings A may be complete rings but to facilitate insertion in the
stuffing box without drawing the rod they are preferably made in semi-circular
segments, the segments of the different rings being arranged so as to break joint
with each other and provision being made by set screws a for keeping the segments
in position and taking up wear. The casing C is provided with end covers c¹ c²
which retain the packing rings in place and make a sliding fit between the
ends E E of the liner so that whilst incapable of end play, it is free to yield to
lateral pressure of the rod in any direction. For this purpose circumferential
clearance is provided between the casing C and the liner D and whilst the
ends E E' bear hard against the liner D which acts as a distance piece between
them this liner D is a shade longer than the casing C so that the ends of the latter
make a steam tight floating fit between the ends E E' of the liner. The outer
end E is retained in place in the stuffing box F by V-pointed set screws e passing
through the sides of the stuffing box and engaging in the V-grooved periphery of
the disc E. This disc E also forms the bottom of the space G in which one or
two turns of soft packing is compressed by a gland H to retain all moisture for
lubrication.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed I declare that what I
claim is :-
A metallic packing contained in a casing whose ends make a steam-tight floating
fit between the ends of an outer casing contained in the stuffing box, circum-
ferential clearance being left between the two casings so that the packing is free
to yield laterally to the pressure of the rod thereby reducing friction and wear as
specified.
Dated this 29th day of July 1896.
A. M. & WM. CLARK,
53, Chancery Lane, London, Chartered Patent Agents.