Improvements in and relating to Packing for Pistons, Plungers, and the like.
Year: 1899

page_text: Date of Application, 4th Sept., 1899-Accepted, 2nd Dec., 1899
COMPLETE SPECIFICATION.
Improvements in and relating to Packing for Pistons, Plungers, and
the like.
We, WILLIAM ROADMAN and LEMON BYERS, Gentlemen, residing, respectively,
in Kregar and Ligonier, in the County of Westmoreland, and State of Pennsyl-
vania, in the United States of America, 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 pistons, plungers and the like adapted to reciprocate
in a cylinder or barrel and requiring a close fit and steam tight joint so as to
obviate a waste of energy and fuel and prevents any cushioning.
The invention consists of a head having an annular chamber in one face
near its periphery, a follower and expander located in the annular chamber and
seated against springs, an expansible metallic packing ring having an inner
beveled seat to receive the conical portion of the expander, the head having the
central portion raised or projected beyond the plane of the edge to receive the
follower, the expander and the expansible packing ring, and the said annular
chamber having ports leading therefrom through the outer face of the head for
the admission of the fluid medium whereby the packing is automatically expanded
when the piston or plunger is in operation.
The improvement also consists of the novel features, details of construction.
and combinations of parts which hereinafter will be more fully set forth, illustrated
and finally claimed.
The drawings show two heads applied to a single rod, and this number may
he varied according to the extent of the piston or plunger and the nature of
the work for which it is designed, and other changes in the form, proportion
and minor details of construction may be resorted to without departing from the
spirit or sacrificing any of the advantages of the invention.
In the drawings:-
Fig. 1 is a longitudinal section of a piston composed of two heads, one of the
latter being shown in section.
Fig. 2 is a plan view of a head.
Fig. 3 is a detail view of the follower, gasket, expander and expansible packing
in perspective and disposed in a group in the relation which they will occupy
when assembled.
Fig. 4 is a detail section of a head.
Corresponding and like parts are referred to in the following description and
indicated in all the views of the drawings by the same reference characters.
The rod 1 upon which the elements or parts comprising the piston are mounted
is provided with a shoulder 2 and a threaded end upon which is mounted a
clamp nut 3 for confining said elements between it and the shoulder 2.
Any number of heads may be placed upon the rod 1 according to the purpose
for which the piston, plunger or the like is designed, and as shown two heads
are provided, the one being a substantial duplicate of the other hence a detail
description of one only will be given. Each head 4 has a central opening 5
DQ77

page_text: to receive the rod 1 and an annular chamber 6 in one face to receive the follower 7
and expander 8. The central portion of the head upon the chambered side is
raised, or projected a short distance beyond the plane of the edge of the portion
exterior to the chamber so as to receive the parts 7 and 8 with the interposed
gasket or packing ring 9. A series of springs 10 are located in the chamber 6
and are secured in depressions or seats formed in the bottom thereof. These
springs support the follower 7 and press it and the expander 8 outward. Ports 11
are formed in the head 4 and communicate with the annular chamber 6 and admit
the motive or fluid medium into said chamber when the piston or the like is
in operation so as to exert an outward pressure against the follower 7 and force
the expander 8 against the sectional packing 12 to expand it and maintain a
steam tight joint or close fit between said packing and the walls of the cylinder
or barrel in which the piston or plunger is located.
The follower 7 is a metallic ring of a width corresponding to the distance
between the walls of the chamber 6 so as to fit snugly therein. The expander 8
is a metallic ring equal in width and diametrical extent to the follower 7 so
as to fit snugly within the annular chamber 6. The outer side of the expander
is made conical to operate by a wedging action when expanding the sectional
packing ring 12. A gasket or packing ring 9 of compressed paper, leather,
rubber or like material is interposed between the follower and expander and its
edges bear against the walls of the chamber 6 so as to prevent the escape of
the fluid medium when confined within the said chamber 6 and exerting an
outward pressure against the follower 7.
The expansible packing ring 12 is composed of a number of sections having
their meeting or matching ends halved, whereby provision is had for variation
in the diametrical extent of said packing without the formation of any space
between the extremities of adjacent sections for the escape of the fluid or motive
medium. The side of the packing ring 12 adjacent to the expander is beveled
or formed with a conical seat to receive the conical end of the expander, whereby
when the latter is pressed outward the inclined surface of the sections riding
upon the sloping walls of the expander will result in increasing the size of
the packing ring 12, whereby its outer edge will be brought into engagement
with the walls of the cylinder or barrel and maintain a close joint therewith.
A cap plate 13 is secured to the chambered face of the head and holds the
expansible packing, the expander, the gasket and the follower in proper position
when assembled: "When two heads are provided, as shown, it is only necessary
to secure the cap plate to one of the heads, as it will form a closure or retainer
for the movable parts applied to the other head because of its disposition, being
located between the two heads and common to each. When the piston is used
in the cylinder of an engine and is alternately subjected to pressure upon
opposite sides it is essential that two heads be provided and arranged upon the
rod with their chambered faces subjacent and with their ported faces outer-
most so as to admit of the motive agent entering the chambers 6 and forcing
the follower and expander outward or against the expansible packing ring to
maintain a steam tight joint between the piston and cylinder.
Having now particularly described and ascertained the nature of our said in-
vention, and in what manner the same is to be performed, we declare that what we
claim is:
1
1. In a device of the character set forth, a head having an annular chamber
in one face near its outer edge, springs located in said chamber, a follower
arranged within said chamber and seated against the springs, an expander placed
against the follower and having its outer side made conical, an expansible packing
ring composed of sections having their meeting or matching ends halved, and
having the sides adjacent to the expander formed with a conical depression to
receive the conical end of said expander, and means for holding the parts in
fixed relation when assembled, substantially as set forth.

page_text: 2. In a device of the character specified, a head formed in one face with an
annular chamber having ports leading therefrom, springs located in said chamber,
a follower seated upon said springs, an expander placed upon the follower_and
having its outer end made conical, an expansible packing ring composed of
sections having their meeting ends halved and the side adjacent to the expander
formed with a conical depression to receive the conical end of the expander and
co-operate therewith, and a cap plate, as and for the purpose described.
3. In a device of the character specified, a head formed in one face with an
annular chamber having ports leading therefrom and having the middle portion
raised or projecting beyond the plane of the edge portion exterior to the annular
chamber, springs located in said chamber, a follower, an expander, a sectional
packing ring, and a cap plate seated against said central portion of the head
and maintaining 'the parts in proper relation, substantially as set forth.
4. In combination, a rod having a threaded extremity and an outer shoulder
a distance from the threaded end, two heads placed upon the rod and having
their inner faces formed with corresponding annular chambers near their outer
edges and having their middle portions raised or projected, and having ports
extending through the outer faces and communicating with the annular chambers,
corresponding followers and expanders for the heads, gaskets or packing rings
interposed between the followers and expanders, springs located in the annular
chambers and exerting an outward pressure against the followers, and expansible
packing rings composed of sections having conical depressions in the sides
adjacent to the expanders to receive the conical ends thereof, a cap plate common
to both heads and interposed between them and secured directly to one of said
heads, and a clamp nut applied to the threaded extremity of the rod to hold the
heads and adjunctive parts in assembled relation, substantially as set forth.
Dated this 4th day of September 1899.
JENSEN & SON,
77, Chancery Lane, London, W.C., Patent Agents.