Improvements in or relating to Stuffing-boxes for Piston Rods, Valve Spindles, and the like.
Year: 1891

page_text: COMPLETE SPECIFICATION,
Improvements in or relating to Stuffing-boxes for Piston Rods, Valve
Spindles, and the like.
We, JAMES MUSGRAVE Junior of the firm of John Musgrave and Sons
"Limited" of Globe Iron Works, Engineers, Millwrights, and Ironfounders, and
JOHN CROMPTON of 9 Grafton Street, Engineers' Draughtsman, both of Bolton
in the County of Lancaster, do hereby declare the nature of our said 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 refers to improvements in or relating to stuffing-boxes for piston
rods, valve spindles, and the like for steam and other motive-power engines,
pumps, hydraulic, and other machinery, and has for its object that of making a
tight joint, and to allow the same to accommodate itself bodily to the deviations or
vibrations of the rod or spindle passing through the packing in case of wear or other
causes.
This we accomplish by making the stuffing-box in one piece and separate
from the cylinder, cover, or other parts, and provide a seating on the outside of
the former which bears against a seating formed on a loose ring secured to the
cylinder, cover, or other part by means of studs and nuts; sufficient latitude being
allowed between the stuffing-box and loose ring to allow for the requisite movement
of rod or spindle. The two seatings are kept together, to form a tight joint by
the pressure in the cylinder, valve-box, or other part the stuffing-box may be
applied to. The inner end of the stuffing-box also forms a seating against a ring
or block which fits in the cylinder end, cover, or other part; the said ring or
block being pressed against the inner end of the stuffing-box by means of springs
scated in recesses.
The springs are made sufficiently strong to resist outside
atmospheric pressure when a vacuum or partial vacuum is formed in the cylinder
or other part it is connected to. The stuffing-box can be used for either metallic
packing, or any ordinary soft or elastic packing, and a gland is employed in the
ordinary manner to press the packing against the rod or spindle. Owing to the
stuffing-box being loose in the ring attached to the cylinder, cover, or other part
it is free to rotate round the rod or spindle of its own account, or it can be rotated
by hand at will; no mechanical means being necessary to operate the same.
Fig. 1 is a sectional elevation of our invention as applied to an old cylinder
cover, and provided with metallic packing and a ring of soft packing to produce
elasticity, and
Fig. 2 is a sectional elevation of our said invention as applied to new cylinder
covers with any ordinary soft or clastic packing in the stuffing-box.
The same letters are employed to indicate corresponding parts in both figures.
A represents a piston rod, valve spindle, or other rod employed in steam and
other motive-power engines, pumps, hydraulic, and other machinery; B is the
ordinary stuffing-box or preparation to receive our improved stuffing-box C; D is
a loose ring; E the gland for operating and holding the packing in stuffing-box;
Fa ring or block; G, G, are springs to maintain the ring or block F in position ;
H, H, are metallic packing rings, and I elastic or soft packing.
In the ordinary stuffing-box or preparation B on the cylinder end, cover, or other
part J we dispose the ring or block F provided with the recesses K to receive the
springs G. Against the outer face I of the ring or block F is placed the end S
of the stuffing-box C. The latter is provided with the faced ring M which sits
against the internal facing N on the loose ring D: this ring is secured to the
stuffing-box or preparation B by the set screws or stud bolts O.
facings L, M, N, and S are truly turned and scraped or prepared with plane
го
The

page_text: surfaces to make them joint tight, and are at right angles to the centre line of
motion of the rod or spindle A to allow the stuffing-box C and packing to move
according to the deviations or vibrations of the rod or spindle A. To further
facilitate the latter the internal diameter of the ring or block F and the opening R
in the loose ring D are made larger than the diameter of the rod or spindle. A
and the outside of the stuffing-box C respectively. The inner end S of the
stuffing-box C and the facings M and N are made sufficiently large to allow of
the stuffing-box moving to the deviations or vibrations of the rod or spindle A
without breaking joint. The facings or seatings M and N are kept together to
form a tight joint by the pressure in the cylinder or other part operating on the
facing S or on the backside of flange M of the stuffing-box C. The ring or
block F is held against the stuffing-box C by means of the springs G, which, in
the case of high-pressure cylinders, may be of light construction with only sufficient
resistance to keep the ring or block F in position against the stuffing-box
facing S.
In applying this stuffing-box to condensing engine or other cylinders
or other machinery where a vacuum or partial vacuum is created the springs G
are provided sufficiently strong to resist or prevent outside atmospheric pressure
forcing the facings M and N as under.. The outer end of the stuffing-box C is
fitted with the loose flange P to allow of the loose ring D being placed in position
over the same. The gland E is secured in position to depress the packing I, or
packing rings H. against the rod or spindle A by means of the stud bolts and
nuts secured to the flange P. The movable stuffing-box C can be supplied
with either metallic or any ordinary soft or elastic packing or a combination of
both as shown in the drawings, and is held in position and pressed against the rod
or spindle A by the gland E and stud bolts and muts Q.
Having now particularly described and ascertained the nature of our said inven-
tion, and in what manner the same is to be performed, we declare that what
we claim is :-
1. The general arrangement, construction, and combination of parts composing
the improved stuffing-box for piston rods, valve spindles, and the like, as herein-
before described and as illustrated in the annexed drawings.
2. The stuffing-box C composed of one piece having the single faced ring M,
the latter being forced against the facing N of the ring D by spring or other
pressure to make a tight joint to prevent the escape of steam or other pressure
and to exclude atmospheric air in case of vacuum or partial vacuum, with means to
allow the stuffing-box to move at right angles to the centre line of motion of the
rod or spindle A according to the deviations or vibrations of the same, substantially
as described.
Detalhe Lil W 1001
EDMUND CHADWICK,
Agent.